Monographs Details: Phellinus lamaensis (Murrill) Pat.
Authority: Fidalgo, Oswaldo & Fidalgo, Maria E. 1968. Polyporaceae from Venezuela. I. Mem. New York Bot. Gard. 17 (2): 1--34.
Description:Species Description - MACROSCOPIC CHARACTERS. sporophore: sessile, eflused-reflexed, imbricate or more rarely, entirely resupinate. pileus: dimidiate, subspathulate or lobate, thin to thick, 2-10 cm long, 4-18 cm wide and 0.3-3 cm thick, abhymenial surface: horny-encrusted, concentrically zonate and sulcate, not cracking on drying, somewhat velutinate in young specimens, blackish-brown at the center, MP-15C12 (Clove) to JMP-8A9 (Hudson Seal) to ferruginous near the margin, MP-15A9 (Dark Beaver), margin: entire, obtuse, lobate in large specimens, MP-14E6, near Stag, context: woody, firm, 5-10 mm thick, varying from bright yellow-brown, MP-12L7 (Burnished Gold), in young specimens, but in mature fruiting bodies more frequently between MP-12K8 (Spruce Y) to MP-14D10 (Mustard Br +) to much darker in old specimens, showing white mycelial strands, radially oriented and more concentrated at its medium portion; more rarely with black lines; limited by a black crust, 0.2-1.2 mm thick, at the surface; with KOH the trama turns blac. TUBES: in several layers, up to 11 mm thick, pruinate, much darker than the context, MP-15A8 (Winter Leaf), poroid surface: cinereous- brown, MP-15E7 (Acorn) to MP-14C6 (Caucasia + ); pores small, regular, circular, (5-)6-7(-8) per mm, (100-)110-140(-170) µ diam; dissepiments entire, acute to obtuse, (25-)50-100(-140) µ thick. MICROSCOPIC CHARACTERS. surface: formed by a trichoderm in young stages and, just a little later, by a crustiform cortex with agglutinated generative hyphae predominating, but setal skeletal hyphae also present; encrustation beginning near the margin, inside the context and visible with unaided eye as a thin black line in section, gradually emerging and forming the crustiform cortex by the disappearance of a nonencrusted layer of generative hyphae situated over it and in young specimens giving to the surface or to the margin a velutinate aspect, later falling out; in the encrusted portion the hyphae not presenting a clear, definite orientation, being sometimes mostly periclinally arranged near the margin and gradually changing to an anticlinal orientation toward the center of the pileus, approaching to a palisadoderm. context: hyphal system dimitic; generative hyphae subhyaline to yellowish, thin- to somewhat thick-walled, branched, tortuous, frequently collapsed when thin-walled, with simple septa, (1.5-)2-3(-4) µ diam; setal skeletal hyphae present, abundant, yellow to nearly ferruginous, thick-walled, 4-7.5 µ diam, up to 110(-200) µ long, with a distinct lumen, showing at times some simple septa and ending with an obtuse tip and mostly prolonged from a solid base beginning in a simple cross-wall; white strands formed only by generative hyphae, completely hyaline, thin-walled, branched, mostly collapsed, (1.5-)3.5-7(-9) µ diam, with simple septa and at times with short projections near the septa and when slender showing many inflations, disappearing progressively as they become wider, dissepiments: setal skeletal hyphae yellow to pale ferruginous, obtuse, 5-7 µ diam and up to 100 µ long, abundant at any part of the dissepiment and frequently projecting into the lumen of the tubes, hymenium: hyphal pegs and cystidia not seen; hymenial setae conical to subulate, obtuse to near acute with straight tips, yellow to near ferruginous, 5-7 µ diam at the hymenium level and projecting beyond the basidia (7-) 13.5-24.5(-30) µ being in its complete size (18-)20-30(-40) X 5-7 µ; basidia honeycomb-type, hyaline, 4-sterigmate, 9-14 X 3.5-4.5 µ, alveoles 3-4.5 µ diam; basidiospores small, subglobose or broadly elhpsoid, thin-walled, smooth, at first hyaline but darkening with age, uniguttulate, nonamyloid, 3-3.5 X 2.5-3 µ.
Distribution and Ecology - Distribution. Phellinus lamaensis has been reported from continental Asia: China (Teng, 1939: 365-366), Burma (Padwick, 1939: 256-258), Malayan Federation (Lloyd, 1924: 1299; Corner, 1932: 335-336), India (Bose, 1924: 137, 1937: 129; Padwick, 1939: 256-258; Tunstall, 1940a: 8; Prasad, 1950: 23; Bagchee, 1952: 540-546, 1954: 141-145) and Aletnam in Tonkin (Lloyd, 1915: 245) ; from the islands of South Andaman (Singh, Singh & Bakshi, 1981: 248); from Ceylon (Lloyd, 1919: 13; Bose, 1924: 137; Murray, 1930: 9) ; from Java (Lloyd, 1915: 245, 1924: 1243; Bose, 1924: 137) ; from Sumatra (Corner, 1932: 335-336); from Borneo (Corner, 1932: 335-336); from the Philippines (Murrill, 1907: 479, 1908b: 412; Bresadola cl- Sydow. 1914: 346; Patouillard, 1914: 2249, 1915: 95; Graff, 1914: 237, 1922: 291; Lloyd, 1915: 245, 1921: 1087; Sydow & Sydow, 1917: 167; Reinking, 1921: 98; Bose, 1924: 137; Teodoro & Gomez, 1926: 249; Teodoro, 1937: 302; Corner, 1932: 335-336); from Japan (Yasuda, 1916: 350; Imazeki, 1943: 107) ; and from New Guinea (Varughese, 1934: 95; Imazeki, 1952: 100-101; Dumbleton, 1954: 431; and in Melanesia from New Caledonia (Dumbleton, 1954: 43). From Africa it has been reported from Kenya (Nattrass, 1961: 9), Eritrea (Castellani & Ciferri, 1950: 28, 43), Tanganyika (AVallace, 1937: 96), Sierra Leone (Deighton, 1930: 30), Ghana (Piening, 1962: 33), Ivory Coast (Resplandy, Chevaugeon, Delassus & Luc, 1954: 2, 3, 4; Roger, 1951: 1050), French Equatorial Africa (Saccas, 1953: 254-255), Cameroon (Pascalet, 1934: 21-22) and Belgian Congo (Everaerts, 1938: 8). In the New World it has been reported in the West Indies from Puerto Rico (Lloyd, 1917: 14), in Central America from Guatemala (Alvarado, 1935: 324) and in South America from Brazil (Bondar, 1940: 135; Torrend, 1940: 328). So far, I a m able to confirm the presence of Phellinus lamaensis in the New World only from Cuba. In different herbaria I found several collections from the New World under this name, but only one belonged to this species. At BPI, I located the material on which Paris (1927: 83-94) based his report on the "zonate foot rot" of sugar cane from Cuba; I found it to be P. lamaensis (for details see in P pachyphloeus). In the Lloyd collection at BPI one collection from Puerto Rico identified by Lloyd (Stevenson 3734) as P. lamaensis proved to be P. noxius.
Distribution and Ecology - Habitat, Hosts and Economic Importance. Although closely related to Phellinus pachyphloeus and P. noxius and morphologically somewhat similar to these species. Corner (1932) pointed out as one of the basic differences which may distinguish P. lamaensis from its allies is its saprophytic behavior. As reported by Corner (1932: 343), the brown root-rot of rubber trees and possibly also the brown root-rot of tea-bushes and the stem-rot of the oil palms are due to P. noxius and not to P. lamaensis. In opposition, Palm (1943: 200-201) described P. lamaensis as a virulent pathogen of tea and Hevea root-rot in the tropics, and Imazeki (1952: 100-101) also indicated that it is known as the causal fungus of the brown-root-rot disease of Para rubber trees. Pascalet (1934: 21-22) reported it as one of the saprophytes on Coffea sp. and Padwick (1939: 256-258) states that P. lamaensis is responsible for honeycombed rot of sapwood and heart wood of Shorea robusta Gaertn. f. and this was supported by Bagchee (1952: 540-546) who mentioned it as the cause of root- and collar-rot of the same host. Young (1954) stated that the brown-root-rot disease of Hevea caused by P. lamaensis is different than that produced by P. norius. According to him, P. noxius does not produce the encrustations on the root and is found under drier conditions and in open plantations, whereas P. lamaensis produces encrustations on the roots of the attacked plants and appears to prefer wetter areas and shaded, thickly growing conditions. When old, P. lamaensis forms a thick brown or blackish felted crust up to 1 inch (2.55 cm) thick on the surface of the roots. On the outer surface the crust develops a thin, brittle, blackish layer but internally it remains brown; the disease is a slowly developing one and by the time symptoms appear it is usually too late to save the host. The Fomes indicated by Paris (1927: ,s3-94) as responsible for the "zonate foot rot" of sugar cane was found to be P lamaensis. In his paper, Paris (1927) gave detailed information about the disease, the way of infection, and fungus growth. Bose (1924: 145) mentioned the species as frequent in tlie mangrove at Sundaribans, Bengal, where the dominant vegetation is represented by members of the RHIZOPHORACEAE. Thus the data about the parasitic behavior of P lamaensis are very contradictory. However, its connection with wood decay of flowering plants and especially on some cultivated ones indicates its great economic importance. It has been reported on a large number of angiosperms However due to certain similarities and confusions between P. lamaensis and P norius the reports may be a little mixed. The following hosts have been reported- BIGNONIACEAE: Tecoma sp. (Pasquier, 1933); COMBRETACEAE: TerminaUa paniculata Roth (Bagchee & Singh, 1960), T. tomentosa AVight & Arn (Bagchee & Singh, 1960); DIPTEROCARPACEAE: Dipterocarpus turbinatus Gaertn. f. (Bagchee, 1954; Bagchee & Singh, 1960), Hopea parviflora Bedd. (Bagchee, 1954; Bagchee & Singh, 1960), Shorea robusta Gaertn. f. (Padwick, 1939; Khan, 1952; Bagchee, 1952, 1953, 1954; Bagchee & Singh, 1960); EUPHORBIACEAE: Aleurites fordii VLemsl. (Prasad, 1950), Hevea brasiliensis (H.B.K.) Müll. Arg. (Weir, 1926; Park, 1929; Murray, 1930; Saccas, 1953; Bagchee & Singh, 1960), H. pseudoferreum ? (Leefmans, 1930), Macaranga denticulata Müll. Arg. in D C . (Bagchee, 1954) ; FAGACEAE: Quercus sp. (Marilao, BPI 10368); GRAMINEAE: Saccharum officinarum L. (BPI, and reported by Paris, 1927: 83-94, as Fomes sp.; Paris sn. Mar 1929, BPI); GUTTIFERAE: Garcinia mangostana L. (Bagchee, 1954), Mesua ferrea L. (Bagchee, 1954); LAURACEAE: Cinnamomum caniphora CL.) T. Nees & Eberm. (Pasquier, 1933; Bagchee, 1954); LEGUMINOSAE: Acacia decurrens (AA-endl.) Willd. (Leefmans, 1930; Steinmann, 1930), Albizzia chinensis Merrill (Steinmann, 1931), A. falcata Backer ex Merrill (Steinmann, 1931; Park, 1933), A. integrifolia ? (Bagchee, 1954), A. lebbek Benth. (Resplandy, Chevaugeon, Delassus & Luc, 1954), A. stipulata Boiv. (Bagchee, 1954), Cassia sp. (Roger, 1951), Dalbergia sp. (Tunstall, 1930; Pasquier, 1933; Roger, 1951), Erythrina indica Lam. (Roger, 1951), E. lithosperma Blume ex Miq. (Park, 1932), E. subumbrans Merrill (Steinmann, 1931), GUricidia maculata H.B.K. (Park, 1932, 1933), Leucaena glauca Benth. (Leefmans, 1929, 1930; Steinmann, 1930, 1931; Pasquier, 1933), Poinciana regia Boj. ex Hook. (Bagchee, 1954), Tephrosia Candida DC. (Steinmann, 1931; Park, 1932; Pasquier, 1933); MALVACEAE: Eriodendron anfractuosum DC. (Bagchee, 1954) and as Ceiba pentandra Gaertn. f. (Leefmans, 1930); MELIACEAE: Melia azedarach L. (Roger, 1951), Sivietenia macrophylla King (Park, 1933); MORACEAE: Artocarpus indica ? (Bagchee, 1954), Ficus sp. (Cunningham, 1965), Ficus religiosa L. (Park, 1934); PALMAE: Cocos nucifera L. (Pasquier, 1933; Varughese, 1934), Elaeis guineensis Jacq. (Roger, 1951); PROTEACEAE: Grevillea robusta A. Cunn. in R. Br. (Park, 1932; Roger, 1951; Bagchee, 1954); RUBIACEAE: Cinchona sp. (Bagchee Sz Singh, 1960), Coffea abeokutae Cramer (Resplandy, Chevaugeon, Delassus & Luc, 1954), C. arabica L. (Keuchenius, 1931; Van der Goot, 1934; Everaerts, 1938; Bagchee & Singh, 1960), C. robusta Linden. (Park, 1933); STERCULIACEAE: Bichea acuminata (Beauv.) Farwell (Deighton, 1930), Sterculia alata Roxb. (Bagchee ct Singh, 1960), Theobroma cacao L. (Leefmans, 1930; Pasquier, 1933; Park, 1934); THEACEAE: Thea sinensis L. (Tunstall, 1930, 1940b; Pasquier, 1933; Van der Goot, 1934; Nagorny, 1938; and as Camellia thea Link, Bagchee & Singh, 1960), Schima uallichi Choisy (Bagchee, 1954; Bagchee k Singh, 1960); URTICACEAE: Castilloa sp. (Roger, 1951).
Figs. 5, 6,44r-52.
Pyropolyporus lamaensis Murr., Bull. Torrey Club 34(9): 479. 1907, 35(8): 412. 1908. Fomes lamaensis (Murr.) Sacc. & Trott. in Sacc, Syll. Fung. 21: 287. 1912; Graff, Philip. Jour. Sci. 9(3): 237. 1914; Lloyd, Mycol. Writ. 4(Syn. Gen. Fomes): 245. 1915; Yasuda, Bot. Mag. Tokyo 30: 350. 1916; Lloyd, Mycol. AVrit. 5 (Lett. 65): 14, note 559. 1917, 5(Lett. 69): 13, note 793. 1919, 6(Mycol. Not. 65): 1087, note 1011. 1921; Reinking, Philip. Jour. Sci. 19(1): 98. 1921; Graff, Bull. Torrey Club 48(11): 291. 1922; Bose, Rev. Path. Veg. Ent. Agric. 11(2): 137, 145. 1924; Teodoro & Gomez, Philip. Agr. Rev. 19(3): 249. 1926; Weir, U. S. Dep. Agr. Bull. 1380: 84. 1926; Small, Brit. Mycol. Soc. Trans. 13(1-2): 60-61. 1928; Anon., Trop. Agr. 72: 347-359. 1929; Hand. Ind. Tea Assoc. 1929: 45-53. 1929; Park, Ceylon Dep. Agr. Tech. Rep. 1928: 1-9. 1929; Bally, Bergcultures 3(65): 1669-1675. 1929; Constantin, Ann. Sci. Nat. Bot. X. 11: xii. 1929; Gadd, Trop. Agr. 6: 106-109. 1929; Brit. Mycol. Soc. Trans. 14(1-2): 104. 1928; Leefmans, Meded. Inst. Plantenziekt. 75: 1-96. 1929; McDonald, an-Afric. Agr. Veter. Conf. Pretoria 2: 250-252. 1929; Bull. Dep. Agr. Kenya 7h: 1-3. 1929, 21: 16. 1929; Mitchell, Rep. Exec. Comm. Rubb. Res. Scheme 7: 9-11. 1929; Staner, Pan-Afric. Agr. Veter. Conf. Pretoria 2: 222-233. 1929; Bally, Arch. Kotiiecult. 4(1): 1-16. 1930; Deighton, Ann. Rep. Dep. Agr. Sierra Leone 1930: 30. 1930; Leefmans. Meded. Inst. Plantenziekt. 79: 74, 75. 1930; Murray, Rubb. Res. Scheme 1929: 5-8. 1930, 1930: 9. 1930; Peelen, Bergcultures 4(22): 573-580. 1930; Sharpies & Jorgensen, Malayan Agr. Jour. 18(4): 184-187. 1830; Staner. Bull. Agr. Congo Belg. 21(3): 649-658. 1930; Steinmann, Bergcultures 4(16): 403-405. 1930; Tilemans, Bull. Agr. Congo Belg. 21(4): 1196-1202. 1930; Tunstall, Quart. Jour. Indian Tea Assoc. 1: 28. 1930, 4: 194. 1930; Zboray, Bergcultures 4(29): 758-763. 1930; Keuchenius, Bergcultures 5(8): 203-204. 1931; Leefmans, Meded. Inst. Plantenziekt. 82: 68, 73, 75. 77, 90, 99. 1931; Steinmann, Bergcultures 5(10): 255-257. 1931; Thompson, Fed. Malay States Dep. Agr. Sci. Ser. 6: 8. 1931; Corner, Gard. Buh. Straits Settlem. 5(12): 333-341. 1932; Brit. Mycol. Soc. Trans. 17(1-2): 51. 1932; Bugnicourt, Bull. Econ. Indochine, B. 35: 512. 1932; Park, Trop. Agr. 78(2): 79, 80, 81. 1932; Ceylon Dep. Agr. Adm. Rep. 1932: D-116, D-117, D-119, D-120. 1933; Mallamaire, Intern. Bull. Plant Protect. 7(12): 266. 1933; Pasquier, Bull. Econ. Indochine, B. 36: 78. 1933; Park, Ceylon Dep. Agr. Adm. Rep. 1933: 127, 129. 1934; Van der Goot, Meded. Inst. Plantenziekt. 83: 71, 79. 1934; Varughese, Dep. Agr. Fish. Travancore 1934: 95. 1934; Alvarado, Trat. Cahcult. Pract. 1935: 324. 1935; MacMillan, Trop. Pl. Gard. 472. 1935; Psaltze, Bergcultures 9(37): 851. 1935; Tempany, Ann. Rep. Dep. Agr. Malay States 1935: 65. 1935; Teng, Sinensia 7(2): 234. 1936; Sturdv, Tanganyika Terr. Dep. Agr., Ann. Rep. 1936: 10. 1937. Teodoro, Enum. Phihp. Fung. 302. 1937; Bose, Ann. Mycol. 35(2): 129. 1937; Wallace, Tanganyika Terr. Dep. Agr., Ann. Rep. 1936: 96. 1937; Everaerts, Agr. Elev. Congo Belg. 12(1): 8. 1938; Nagorny, Bulb Georgian Exp. Sta. Pl. Protect. 1: 5. 1938; Teng, Contr. Knowl. High. Fungi China 365-366. 1939; Thompson, Malayan Agr. Jour. 27(3): 87. 1939; Bondar, Bol. Inst. Centr. Fom. Econ. Bahia 8: 135. 1940; Torrend, An. Prim. Reun. S. Am. Bot. 2: 328 (1938). 1940; Tunstall, Indian Tea Mem. 8: 8, 24. 1940; Staner, Inst. Roy. Colon Belg. Mem. 11: 11. 1941; Wallace, Tanganyika Terr. Dep. Agr. Mycol. Circ. 20: 1-5. 1947; Castellani & Ciferri, Atti Suppl. Inst. Bot. Univ. Pavia, V. H: 28, 43 1950; Prasad, Indian For. Rec. 8(1): 23. 1950; Khan, Pakistan Jour Sci 4: 73 1952; Bagchee, Indian For. 78(11): 541. 1952; Thompson & Johnston, Mycol Pap. Commonw. Mycol. Inst. 52: 15. 1953; Bagchee, Indian For. Rec. 1(2): 20. 1953 1(8): 141-145. 1954; Resplandy, Chevaugeon, Delassus & Luc, Ann. Epiphyt. 5(1): 2, 3, 4. 1954; Young, Rubb. Res. Inst. Ceylon Adv. Circ. 48: 2 p. 1954; Rubb Res. Inst Ceylon Quart. Circ. 31(1): 15 1955; Nattrass, Mycol. Pap. Common. Mycol. Inst. 81: 9. 1961; Singh & Bakshi, Indian For. 87(4): 248. 1961; Piening. Ghana Min. Agr. Bulh 2: 33. 1962 (variant spellings: Fomes lamaoensis, F. lamaopensis, F. lamacensis, F. lamaonensis and F. Lamaenensis).
Fomes lamaensis (Murr.) Sacc. & Trott. var. secedens Corner, Garde. Bull. Straits Settlem. 5(12): 341-342. 1932; Thompson & Johnson, Mycol. Pap. Commonw. Mycol. Inst. 1953. Type from Pahang (Padang Piol), Malayan Federation, Corner, Sing Field 24489 (NY, BPI).
Inonotus lamaensis (Murr.) Pilat in Kavina & Pilat, Atl. Champ. Eur. 3(66-73): 575. 1942 (incidental mention; not validly pubhshed).
Cryptoderma lamaense (Murr.) Imaz., Bull. Tokyo Sci. Mus. 6: 107. 1943; Bull. Gov. For. Exp. Sta. 57: 101-102. 1952 (variant spelhng: Cryptoderma lamaoense).
Pyropolyporus williamsii Murr., Bull. Torrey Club 34(9): 479. 1907; Leafl. Phihp. Bot. 1: 271. 1908. Type from Lamao River, Mt. Mariveles, Bataan Prov., Luzon I., Phihppine Is., Williams 150 (NY), Lloyd 6860 (BPI).
Fomes williamsii (Murr.) Sacc. A: Trott. in Sacc, Syll. Fung. 21: 289-290. 1912; Bresadola, Hedwigia 53(1): 59. 1912; Bresadola & Sydow, Philip. Jour. Sci. 9(4): 346. 1914; Sydow & Sydow, Ann. Mycol. 15(3-4): 167. 1917.
Pliellinus williamsii (Murr.) Pat., Leafl. Philip. Bot. 6: 2249. 1914; Phihp. Jour Sci 10(2): 95. 1915.
Fomes sublamaensis Lloyd, Mycol. AVrit. 7(Mycol. Not. 66): 1128. 1922. Type from Mt. Maquiling, Laguna Prov., Luzon I., Phihppine Is., Reinking, Lloyd 37762 (BPI).
Type. Holotype, Williams (sn) (NY).
Type Locality. Lamao River, Bataan Prov., Luzon I., Philippine Is.
Basionym. Pyropolyporus lamaensis Murr., 1907.
Illustrations. Corner, Gard. Bull. Straits Settlem. 5(12): text-figs, la, 3b, 4, 5e-f, h-l, 6a, 7. 1932; Imazeki, Bull. Gov. For. Exp. Sta. 5 7 : test-fig. 1, pl. 1, fig. 4. 1952; Bagchee, Indian For. Rec. II. 1(18): pl. XXVIII, text-figs. 1-6. 1954; Singh, Singh & Bakshi, Indian For. 87(4) : figs. 4-6. 1961; Cunningham, Polyp. New Zealand, fig. 50. 1965.
Discussion. Although Phellinus lamaensis can be considered to be a fairly common species, it was first described in 1907 by Murrill when, in the same paper and on the same page, he described it twice under the names of Pyropolyporus lamaensis and P williamsii (Murrill, 1907: 479) both being from the Philippines. Since P. lamaensis appeared first on the page, it became established in the literature with a large number of variant spellings such as lamaoensis, lamaopensis, lamacensis, lamaonensis and lamaenensis. Some years later it was described again, also from the Philippines, under the name of Fomes sublamaensis by Lloyd (1922a: 1128). Types of all three were examined and found to be identical. The species was confused with an unnamed species until Corner (1932) settled properly the differences between it and Phellinus noxius which Corner described. The fundamental difference between the two species is the presence in P. lamaensis of hymenial setae, the absence of such in P. noxius. Other closely related species are P. pachyphloeus, P. magnosporus, P melanodermus and P portoricensis from which P. lamaensis can easily be separated by several characteristics. In P. lamaensis the context always has a distinctly lighter color than the tube layer, and the setal skeletal hyphae of the context are yellow to pale-ferruginous, the tip endings are obtuse and are more or less similar to the skeletal hyphae of other species of Phellinus. Consequently, P lamaensis shows a transition between the regular skeletals and the differentiated seta-like ones found in P. pachyphloeus and its allies. In P. pachyphloeus the context differs slightly in color from the tube layers; the setal skeletal hyphae of the context are ferruginous, a very distinct color, are much larger in diameter than the surrounding generative hyphae and have acute tips. In P. magnosporus the setal skeletal hyphae aro similar to those in P. pachyphloeus; the larger size of pores and spores are the distinctive features of P. magnosporus. Phellinus melanodermus and P. portoricensis are also closely related to P. lamaensis, all three having nearly the same color of tbe context and tubes. The last two show some similarities as well as some differences in the formation of the surface. In both, a layer of agglutinated hvphae appears in the middle of the context, in cross section seen as a black line which in P. lamaensis is much thicker and soon emerges forming the crustiform cortex by the disappearance of a fine layer of generative hyphae situated over it in voung specimens; in P. portoricensis this layer of generative hyphae is much thicker and the black line thinner. In very old specimens the layer represented by this black line may constitute tbe surface. This is the reason why I decided to consider its context to be duplex because the two portions of this context separated by the black line have different structure and texture. The setal skeletal hyphae of P. portoricensis are ferruginous, with acute tips, up to 350 µ long and 18 µ diam while its basidiospores are "yellow even when young" and are more similar to the ones found in P. pachyphloeus. The setal skeletal hyphae of P melanodermus are of this same type; it does not have hymenial setae. I have examined also the type and other specimens from Malaya identified by Corner (1932: 341-342) as Fomes lamaensis var secedens. These specimens have much darker context and represent one of the extremes of variation of this species to which they undoubtedly belong. However the examination of typical specimens of the species revealed characteristics quite close to those established by Corner for the variety. I was unable to establish distinct limits between them. From British North Borneo specimens [A. D. E. Elmer 20498 (NY)] with another extreme of variation were studied which showed the following characteristics: pores circular to subangular, 8-9 per mm, 90-100(-110) µ diam; dissepiments 20-30(-50) µ thick; setal skeletal hyphae yellow to ferruginous, 3-5 µ diam, up to 196 µ long; hymenial setae 14-19 X 3.5-6 µ; basidia forming an irregular honeycomb, 7-8 X 3.5-4.5 µ; basidiospores hyaline, subglobose to elliptic, 3-1 X 2-3 µ diam. I found a great range of variation in the generative hyphae; while they are forming the white hyphal strands of the context, they are always hyaline and thin-walled. The narrower ones have a larger number of inflations, are much branched, and show a greater number of crosswalls. When they become wider, they have more regular form; the inflations disappear and not many branches or crosswalls are seen. From these generative hyphae the ones responsible for the construction of the context differentiate and have the walls somewhat thickened and yellowish, well branched but with a few crosswalls. According to Corner (1932), Phellinus lamaensis may form fruiting bodies up to "28.5 cm in radius and 43 cm wide." In culture, P lamaensis is said to produce conidia (Palm, 1943: 200-201). Cunningham (1965: 220) indicated for P. lamaensis the presence of subclavate paraphyses (?) 8-14 x 3.5-4 µ and in general gave somewhat higher measurements for the microstructures: setae 18-40 X 6-8 µ; basidia 12-18 x 4-5 µ and basidiospores 3.5-4 X 2.5-3 µ.