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On the Occurrence of Aphroceras (Leucandra) c/iarensis 

 Stephens near Plymouth. 



By 

 Arthur Dendy, D.Sc, F.R.S. 



In July, 1912, a paper was published in the Proceedings of the Royal 

 Irish Academy (Vol. XXXI) on the Marine Porifera of Clare Island, by 

 Miss Jane Stephens, in which the authoress gives an excellent account of 

 a new species of Calcareous Sponge, Leucandra cliarensis. In April of 

 the same year I happened to be working at the Marine Laboratory at 

 Plymouth, and my friend Mr. Orton brought me several specimens of a 

 very pretty little calcareous sponge just collected by him at Wembury 

 Bay. I was too much occupied with other work to examine these care- 

 fully at the time, but simply preserved them in spirit. Recently I have 

 examined them in detail, and find, curiously enough, that they belong 

 to the species described by Miss Stephens from Clare Island on the 

 west coast of Ireland. 



It is unnecessary, in view of the description already published by Miss 

 Stephens, to give a detailed account of the sponge in this place. I may, 

 however, point out the salient features by which it is easily recognized. 

 The external appearance is characteristic. The individuals are usually 

 solitary and less than an inch in height. The form of the sponge, how- 

 ever, varies greatly, from cjuite slender to almost globular. There is 

 usually a single terminal vent. The surface, when viewed under a 

 pocket-lens, exhibits a glistening appearance, with longitudinal striations 

 due to the presence of gigantic oxea in the dermal cortex. This arrange- 

 ment of the large oxea brings about a close resemblance to species of the 

 genus Ute. The canal system is, however, typically leuconoid, with 

 small, rounded flagellate characters. 



The most remarkable and constant specific character appsars to be 

 the presence of enormous sabre-shaped apical rays on the gastral quadri- 

 radiates, sometimes reaching a length of 0-5 mm., and, of course, pro- 

 jecting into the gastral cavity. 



In our recently published paper on " The Classification and Phylogeny 



