206 Tranaactions. — Zoology. 



Subdivision 1. — "The exhalent openings through which 

 the water leaves the sponge are true oscula — i.e., they lead 

 directly into a space lined by collared cells, and formed by the 

 union of a number of ascon-tubes." 



Leucosolejiia challengeri. LeiLCOsolenia intermedia. 



„ cerebrum. „ laxa. 



„ proxivia. „ deinessa. 



Subdivision 2. — "The exhalent openings through which 

 the water leaves the sponge are pseudoscula — i.e., they lead at 

 first into a space not lined by collared cells, but, presumably, 

 by ectoderm. This space is a liseudogaster. It really lies 

 outside the colony, and is formed, probably, by the upgrowth 

 of the colony around it. The ascon-tubes open into the pseudo- 

 gaster." Leucosolenia rosea. 



I hope to have an opportunity, in a future paper, of making 

 some remarks on the histology of the New Zealand reticulate 

 ascons. 



Leucosolenia clathrus, Schmidt. ("Supplement der Spou- 

 gien des Adriatisclien Meeres," p. 24.) 



As Mr. Carter has pointed out,''' Schmidt's sponge is not 

 the one afterwards described and figured by Haeckel.t In 

 Haeckel's sponge the ends of the spicules are obtusely rounded, 

 or even knobbed, and the rays are often wavy. 



I see no reason for regarding as different from L. clathrus 

 a white ascon of considerable size that occurs freely along the 

 shores of Cook Strait, in the neighbourhood of Wellington. 

 Its spicules are more sharply pointed than the one figured by 

 Schmidt ; but they are almost exactly like those of a speci- 

 men, sent me by Dr. Dendy, of a sponge collected at Budleigli 

 Salterton by Mr. Carter, and identified by him as Schmidt's 

 L. clathrus. Moreover, the specimen referred to shows meso- 

 dermal ingrowths exactly like those of Wellington specimens 

 — Dendy 's type E. The sponge shov.'s at death the colour- 

 changes described by Carter. 



I also place under L. clathriLS, for the present at all events, 

 the large white ascon that occurs so freely in Paterson's 

 Inlet, Stewart Island. In this handsome sponge the spicules 

 are often blunt, and approach those of L. coriacea, and the 

 mesodermal ingrowths are less pronounced than in the Wel- 

 lington sponge. Moreover, it differs from the Wellington 

 sponge in the fact that its oscules are conspicuous, and borne 

 at the apex of pronounced papillae. 



* A.M.N.H., 5, xiv., p. 17. 



i "Kalkschwjimme," ii., p. 30. 



