1866.] 17 [Agassiz. 



Lives in colonies of from two to several, the bodies attached to the 

 forked terminations of a single stem. 



Salpingaeca, nov. gen., is in general terms, a stemless CodosigOy 

 seated loosely in a variously shajjed calyx ; the former bearing a sim- 

 ilar relation to the latter that Cothurnia does to Epistijlis. Three 

 species to be described in a forthcoming memoir. 



Leucosolenia hotryoides Bowerbank. This species of sponge formed 

 the principal object of investigation in the group to which it belongs, 

 and drawing an inference from it the conclusion was reached that all 

 the true ciliated sponges are flagellate Protozoa. In the present in- 

 stance the '■'■monociliated sponge-cells" as they are called by Carter, are 

 so closely allied to Codosiga, in every point of structure, that one 

 might rightly designate the Leucosolenia as a horde of the stemless 

 monads of Codosiga closely packed together, with their posterior ends 

 imbedded in a gelatiniforra, spiculiferous mass. Each monad pos- 

 sesses a very long flagellum, which arises from the centre of the broad 

 frontal area that is enclosed by the low, cylindrical, extremely deli- 

 cate membranous collar, and is endowed with two distinct, but jux- 

 taposed contractile vesicles. 



Anthophysa Bory, has a prehensile lip, like Monas ; two flagella, of 

 which one is long, stout and arcuate, and the other — attached close 

 to the base of the first — very short and delicate ; a mouth opening 

 between the lip and the flagella; and a contractile vesicle lying (in 

 A, Mulleri Bory) at the middle of the body. 



Mr. W. T. Brigham gave some account of recent investi- 

 gations on the volcanoes of the Hawaiian Islands, exhibiting 

 and presenting a very extensive series of lavas gathered 

 from the different flows, especially of the successive erup- 

 tions of the volcano Kilauea, which were found to vary 

 greatly, both in their physical and chemical characters. He 

 showed stalagmites formed in a cave heated by steam, where 

 the lava had dissolved on the roof of the cave, forming long 

 pendants. 



The following paper was read : — 



.Description of Salpa Cabotti Desor. By Alex. Agassiz. 



The Salpa here described is quite common south of Cape Cod in 

 Vineyard Sound, Buzzard's Bay, and Long Island Sound. I suppose 

 it to be the species named by Desor, Salpa Cabotti, mentioned in the 

 third volume of the Proceedings of the Boston Society of Natural 



FBOCXBDIHeS B. 8. N. H. — VOL. XI. 2 DECEMBER, 1866. 



