202 ♦ 



biciliated. A transverse view presented, thus, a very Staurastrum- 

 like outline. Mr. Archer showed one or two other more or less 

 closely related organisms, as yet hard to identify, if not novel ; and 

 trusted, perhaps, to be able to revert to the first of the foregoing on 

 a future occasion, if, perchance, a search in the same spot, a small 

 rocli-pool at Greystones, whose water supply seemed to be about 

 equally contributed by rain, by ooze from the bank above, and by sea 

 spray, should reveal further examples. 



Dr. E. Perceval Wright exhibited a series of preparations show- 

 ing the form and arrangement of the spicules in Aphrocallistes 

 Hocagei, a new species of this genus, which came from the Cape de 

 Verd Islands. Dr. Wright's observations on this species will be 

 found in extenso in a paper on some new sponges — vide ante, p. 1. 



Professor A. Agassiz stated to the meeting that this interesting 

 species had been found by Count Pourtales off the east coast of 

 America. 



Novemler \Wh, 1869. 



Rev. E. O'Meara exhibited a pretty new diatom belonging to the 

 genus Pinnularia, which he proposed to name Pinniilaria Collissii, 

 in memory of our late lamented Club member Dr. Maurice H. 

 Collis. This he would presently bring forward in detail and figure 

 in the Journal. 



Mr. Archer brought forward an interesting condition of a minute 

 Scytonematous plant. The slender filaments were interwoven in a 

 variety of ways, and gradually tapered off until the extremities 

 became a mere thread, the whole enveloped in a gelatinous matrix, 

 the curious circumstance being that each ultimate extremity or 

 " twig" bore a very minute elliptic cell attached at the extreme point. 

 These cells increased by self-division and appeared to be enveloped 

 by a special definitely bounded gelatinous covering, each presently 

 borne on a stalk of its own, a bifurcation of the supporting filament 

 taking place on each act of self-division. These elliptic cells were 

 not ordinarily attached either by the middle or end, but obliquely, 

 or as it were by the shoulder, so to speak. The whole thus pre- 

 sented somewhat of a tree-like aj^pearance, bearing so many fruit- 

 like structures on its leafless branches. These cells, when isolated, 

 and as they occurred sometimes in the present material, were doubt- 

 less some of Kiitzing's many heterogenous " Palmoglcea," forms such 

 as P. micrococca (Kiitz.). It was interesting here to note the strictly 

 genetic relationship of the cells to the filaments. It ought to be 

 observed here that such forms as the present are completely distinct 

 from the so-called " Palmoglcea macrococca," " P. crassa," 

 "Br6bissonii," &c. Regarding the Scytonemese, as Mr. Archer 

 believed, as true, though aberrant or non-typical lichens, it might 

 be assumed probablj^ in this instance, that these egg-shaped cells at 

 the apices of the filaments were " gonidia " — but what then of the 

 central axis of green matter pervading these plants — likewise here 

 present — which portion of the structure must be considered in Ephebe 

 and others as the equivalent of the " gonidia" of typical lichens ? No 



