296 MR. A. D. COTTON ON 
vegetative parts the cells are as a rule longer than in. those 
parts nearer the fructifieation. The end cells of the short 
lateral branches are often spherical and enlargéd; from the 
material available the significance of these cells is doubtful. The 
pluriloeular sporangia are produced externally, they are simple 
and acutely ovate in outline, they measure 50-70 u long by 
20-25 u long (fig. 5). 
Reinsch’s figure (8. plate 6. a. fig. 2 a) does not by any means 
illustrate the plant. Indeed the cells of the host-plant figured 
hardly suggest B. byssoides at all. Itis fair, however, to Reinsch 
to state that he adds in a note that his other figures (plate 6) 
were accidentally destroyed. 
The present species differs from Streblonema parasiticus, 
Sauv., which occurs in Cystoclonium and Ceramium, by the 
larger sporangia and also by the apparent absence of external 
filaments. In S. parasiticus the later are very conspicuous. 
SrREBLONEMA  ZANARDINII, De Toni.—This species was 
described by Crouan as Ectocarpus (section Streblonema) 
Zanardinii (11. p. 161) ; it occurs in Gastroclonium kaliforme, 
Ardiss. De Toni (6. vol. ili. p. 572) placed it in the genus 
Streblonema. 
The following remarks on this species may be of interest as 
the only information to be obtained as to it, is from the somewhat 
brief original description. 
Very fine material of S. Zanardinii was obtained by the 
author in Gastroclonium kaliforme at Weymouth, April 1905. 
Gastrocloninm was then in vigorous growth, but although that 
was the case it was richly infested by the endophyte, indeed the 
filaments of the latter reached up to the growing apices of the 
Gastroclonium. 
The plurilocular sporangia are very freely produced, and are 
often in pairs ; they are usually 50-60 y in length and 15-20 win 
width. Their general form much resembles that of S. intestinum. 
The short lateral filaments on which they are borne are immersed 
in the gelatinous sheath of the host, and only the sporangium 
proper appears externally. In this respect it differs from many 
species of the genus, but agrees with that last described. A 
few seattered hair-like filaments protrude here and there, but 
except for these and the sporangia, the growth js entirely endo- 
phytic. Abnormalities are somewhat common in this species, 
