BIBLIOGRAPHY. 
119 
whereas they are never met with in L. Laminaria , although very 
occasionally a sterile one is present in the tufts of that species. 
Special interest attaches to that portion of Prof. Johnson’s 
valuable paper which deals with the vegetative reproduction of 
the new species. The author says : — “ Though the filaments of a 
tuft are unbranched, and, to this extent, unconnected with one 
another, they are, at their lower ends, in close contact with one 
another, and more or less fused into a compact body of a sub- 
parencliymatous nature. There are, too, to be observed, growing 
out from the superficial cells at the base of the filaments, rhizoidal 
septate hyphac which come into contact with the surface of the 
Alaria thallus, and can, no doubt, give rise to new Pogotriclnum 
filaments. On making a vertical section through the anchorage 
of Pogotrichum hibernicum it is seen to be not merely applied to 
the surface of the Alaria , i.e ., epiphytic, as a root-disc of. a Fucus 
is to a stone, on which it grows. 
“ The individual filaments of P. hibernicum penetrate into the 
Alaria thallus, creep and ramify between both its cortical and 
medullary cells, the limiting layer of the Alaria being frequently 
obliterated during the process. A close examination of the 
sections gives every indication that these endophytic or intra- 
cortical hyphae can, after creeping for some distance in the Alaria 
thallus, emerge at either surface to form new Pogotrichum tufts.” 
Even supposing P. hibernicum is identical with L. Laminaria , 
a supposition we are not prepared to admit, we think Dr. Johnson 
is to be congratulated on his very interesting discovery of this 
vegetative reproduction by means of stoloniferous endophytic 
hyphac in the genus Litosiphon. The paper is illustrated by a 
good plate, giving figures of the fructification, etc., but unfortu- 
nately not of the endophytic hyphae. E. A. B. 
On the Antheridia, etc., of some Floridea. By T. H. Buffhara, 
A.L.S. (Journal of the Quekett Microscopical Club, Vol. v., 
ser. ii., pp. 291-305, October, 1893). 
This is really a continuation of Mr. Buff ham’s paper on the 
same subject, which appeared in October, 1890, and contains full 
descriptions of the antheridia, the discovery of which was then 
mentioned. The paper is both interesting and valuable, as it 
contains two plates, on which 44 separate figures illustrating 
antheridia, etc., are drawn, and the author assures us that with 
two exceptions, indicated in the proper place, he has drawn 
nothing which has been figured before. The first antheridia 
mentioned are those of Choreocolax Polysiphonia , Beinsch, which 
may be distinguished as bright circular spots about 12 yu, in 
diameter, scattered over the surface of the dark frond. The cells 
bearing pollinoids form a bunch of short incurved threads arising 
from a base of branching cells. Between the bunches are longer 
filaments forming a kind of involucre. This discovery of the 
antheridia of the species, coupled with Mr. H. M. Bichard’s 
