292 T. H. BUFFHAM ON ANTHERTDIA. 



form a bunch of incurving short threads arising from a base of 

 branching cells. The bunch is below a portion of the exterior 

 where the general surface is not indurated, but consists only of 

 the gelatinous investment usual in antheridial layers. Indeed, 

 the bright spots just mentioned as on the surface are over this 

 bunch. Between these bunches are longer filaments forming a 

 kind of involucre (Fig. 2). The male organs of this alga do 

 not appear to have been observed before, although the cysto- 

 carps and tetraspores have been described and drawn by Mr. 

 H. M. Richards {Froc. American Acad, of Arts and Sciences, vol. 

 xxvi.), and I found them very rare in a quantity of Poly, 

 fastigiata infested. (Folkestone, June, 1892, collected by Mr. 

 J. T. Neeve.) 



Harvey ella mirahilis Schmitz et Rke. (Ghoreocolax mirahilis 

 Reinsch. Not in Phyc. Brit.) — This parasite is usually much 

 more conspicuous than the preceding, and is found on Ehodo- 

 mela suhfusca Ag. The male plant forms a group of two to 

 eio-ht rounded lobes, each "S-'S mm. in diam. It may be distin- 

 guished from those bearing other organs (PI. XIV., Figs. 40, 41) 

 by its uniformly brown colour surrounded by a semi-translucent 

 yellowish border (PI. XIII., Fig. 3). A vertical section shows the 

 body of the lobe to be composed of irregularly-rounded cells set 

 in a considerable mass of hyaline substance. A short distance 

 below the surface numerous smaller cells appear, and from 

 these arise tubes about 10 /x Avide, and the pollinoids are seen in 

 these in single or double rows of four to six in length and are 

 emitted from the mouth of the tube at the surface (Fig. 4.) 

 The process appears to be continued by the repeated formation 

 of pollinoids from the lower brown cells, so that a considerable 

 number will be produced from a superficial area of this small 

 size. There are cases in which a similar mode of production 

 exists to a limited extent, but I am not aware of any at all 

 approaching the productive power of this interesting parasitic 

 alga. These organs have been recorded only on the German 

 coast by Schmitz and Reinke. (Deal, February, 1892, collected 

 by Mr. Neeve.) 



Phyllophora ruhens Grev., a membranous plant of very un- 

 attractive aspect to the mere collector, produces antheridia of 

 even elaborate structure. These are subspherical bodies on a 

 thin pedicel, borne at, or just within, the borders of the upper 



