PROCEEDINGS OF SOCIETIES. 



Dublin Miceoscopical Club. 



11th April, 1878. 



Peronospora infesfans ravages, exMhited. — Dr. Moore showed 

 some of the leaf-tissue of the potato permeated by the Perono- 

 spora-pest, in order to point out the manner in which it became 

 thereby disintegrated and killed. 



Dinopliysis norvegica, from Melville Bay, was exhibited by Dr. 

 Moss, E.N. 



Biddulphia Chinensis, from Yeddo Sea, exliilited. — Eev. E. 

 O'Meara exhibited some specimens of Biddulphia Chinensis, 

 Grev., collected by Mr. Moseley, H.M.S. "Challenger," from the 

 surface of the Yeddow Sea, near Yokohama. This in all essen- 

 tial points agreed w'ith Greville's fiijure of the examples gathered 

 in the harbour of Hong-Kong, but in some minor details a differ- 

 ence was noticeable. In the figure referred to the surface of the 

 valve seen in front view is represented as hollowed in the middle, 

 whereas in the specimens exhibited the boundary line is gene- 

 rally straight, and in some cases showed a slight elevation in the 

 middle. Moreover, the processes are more robust and longer 

 than they are represented ia Greville's figure of the species. 



New Closterium from New Jersey. — Mr. Archer showed ex- 

 amples of a Closterium found amongst some Desmidian forms in 

 an old gathering lying iu the Herbarium of Trinity College, 

 Dublin, and made at New Jersey, America, kindly given to Mr. 

 Archer by Professor E. Perceval Wright. On the slide, at first 

 glance seemingly a poor one, there were to be detected no less 

 than forty-three species. The Closterium in question is a very 

 robust form, considerably curved and very strongly striated ; the 

 striae very few. It most approached Closterium costatum, common 

 in this country. Singularly enough, a single example from New 

 Jersey of that species was opportunely on the slide, quite agree- 

 ing with the British and the Irish form, of which he likewise 

 showed a Scotch specimen; and Mr. Archer took the opportunity 

 to contrast it with the new species. This has more of the size 

 and a good deal of the curvature, without the median inflation of 

 Closterium monilife rum ; its striae are much coarser than those of 

 Closterium costatum. Very opportunely, too, there occurred a 

 Zygospore of the new species on the slide; it is large, sub- 

 orbicular, thick-walled, and smooth, seemingly not remaining at 

 all attached to the empty parent-cells. This species Mr. Archer 

 would designate as CI. crassestriatiim. 



