Radaisia laminariae Setch. & N.L.Gardner

• Region

  North America

• Country

  United States of America

• State/Province

  California

• County/Municipio

  San Francisco Co.

• City/Township

  San Francisco

• Locality

  Fort Point, on Laminaria Sinclairii (Harv.) Farlow

• Coordinates

  37.8106, -122.477

• Coordinate Uncertainty (m)

  264.569

• Georeferencing Method

  Georeferencing Quick Reference Guide, Version 2012. Located coordinates of geogr. center of Fort Point. Measured from coord. to farthest extent of the point to find linear extent (253 m). Input info. into MaNIS Georef. Calc. to find uncert. rad. (Bounded Area).

• Geodetic Datum

  WGS84

• Distribution

  Map all specimens of this taxon

Radaisia laminariae Setchell & Gardner, sp.nov.

Univ.Calif.Publ.Bot.6:444. pl.37. f.14-16. 16 Jl 1918.

Thallo prostrato filamentis compactis radiantibusque,
dichotome ant subdichotome ramosis, stricte compacto,
orbicular!, ad 300p. diam.;cellulis filamentorum prostrat-
orum quadratis, 4-4.5}i diam.,per partitiones horizontales
filamenta compacta erectaque producentibus; thallo adulto
50-40)1 crasso; gonidangiis in filamentis erectis termin-
alibus, sphericis aut lente ovalibus, 8-9u diam.;gonidiis
0.8p diam.,partitione simultanea; thallo laete caeruleo-
viridi.

Prostrate portion of the plant consisting of compact,
radiating filaments, dichotomously or subdichotomously
branched, forming a closely compact thallus circular in
outline, up to 300)i diam.;cells of prostrate filaments
quadrate, 4-4.5u diam., giving rise by horizontal divisions
to closely compact, erect filaments; the whole thallus 30-40H
thick; gonidangia terminal on the erect filaments, spherical,
or slightly oval, 8-9ji diam. ;gonidia 0.8ji diam. formed by
simultaneous division; color bright blue-green.

Growing on the terminal portion of the blades of
Laminaria Sinclairii. Fort point, San Francisco, California.
This locality is, so far as I know, the only one in which
this species has been observed. It probably has a much wider
distribution. The host plant extends from the vicinity of
point Conception, California, to Vancouver Island.

I	have presented a brief discussion in the introduction
to this work, page 430, in regard to the relation between the
general Eyella and Badaisia. R. laminariae I have taken to
represent a typical species of the genus, having a single
layer of cells for the base which gives rise to perpendicular,
parallel, unbranched filaments extending away from the host
and bearing each a single terminal gonidangium. The whole
cushion or colony, is in reality a single plant resulting
from the growth of a single gonidium.

The plants of this species start from a single cell,
and by a few divisions a small group of cells is formed.

Around the margin the cells soon begin to arrange them-
selves radially in rows and by divisions in two planes,
radial and tangential, a circular disk, one layer of cells
deep, is formed. The marginal cells enlarge tangentially
and are cut into two cells by a radial wall, the resulting
"filaments" are of equal growth, as a rule, and the fork-
ing thus becomes dichotomous (pl.37, fig.16). plants often
become so closely associated as to form a continuous layer
over the surface of the host. Even under this condition
they have no effect upon the host, so far as death and dis-
integration of the cells are concerned,and hence they are
strictly epiphytic* The erect filaments result from the
horizontal division of the prostrate or basal cells. They
form very dense, compact masses, their cell walls adhering
firmly (pi.37, fig.15). The gonidangia are numerous, spherical
or slightly oval, being transformed terminal cells of the
erect filaments (pi.37, fig.14).

"	^ NEW YOriK.

BOTANICAL
ALGAE DISTRIBUTED FROM THE	GARDEN

HERBARIUM OF THE UNIVERSITY OF CALIFORNIA

28. Radaisia Laminariae S. & G.

On Laminaria Sinclairii (Harv.) Farlow
Fort Point, San Francisco, California.

N. L. Gardner, No. 3158. Dec. 1915.

00953233