264 Miscellaneous. 



gradually causes the disappearance of the partition which separate d 

 the two vesicles. 



In the non-encysted individuals nearly the same phenomena occur. 

 The two NoctUucce unite by their buccal notches, which become 

 gradually effaced; and the tentacles disappear, sometimes by becoming 

 detached, sometimes by their being absorbed into the body. 



Although M. Cienkowski has repeatedly witnessed all the phases 

 of the copulation, and been able to preserve its products alive for two 

 or three days, he has never seen in them any changes which would 

 indicate a commencement of the formation of zoospores. Neverthe- 

 less the dimensions, and the lobate form, of most of the vesicles borne 

 by the disks of zoospores are in favour of their relation to the products 

 of copulation. 



It is difficult, however, to pronounce an opinion as to the nature of 

 this copulation, which seems to have nothing to do with a sexual act, 

 but probably facilitates the formation of zoospores and has much 

 analogy with the formation of the plasmodium in the Myxomycetes. 



M. Cienkowski concludes, from the sarcodic nature of the contents 

 of the NoctUucce, from the presence of the flagellum discovered by 

 Krohn, and, finally, from the occurrence of a reproduction by active 

 zoospores, that this organism must take its place in the class of the 

 Flagellata, in which it should form a distinct group, in consequence of 

 its striated tentacle. — Archivfur miJcr. Anat. ix. (1872) p. 47; Bibl. 

 Univ. 1873, Bull. Sci. p. 167. 



Natal Sponges. By Dr. J. E. Gray, F.E.S. &c. 



In the Proc. Zool. Soc. 1873, pp. 17 & 21, Dr. Bowerbank has 

 described two sponges, which he says were received from his friend 

 Captain Charles Tyler, " who obtained them from Port Elizabeth." 

 Captain Tyler kindly informs me that he bought these sponges of 

 Mr. Cutter. The British Museum had the first pick of this collection 

 from Port Elizabeth, so that they are both in the British Museum. 



1. Leuconia glomerosa, Bowerbank (P. Z. S. 1873, p. 17, t. iv.), is 

 the same as the species I long ago described and figured under the 

 name of Aphroceras alcicornis (P. Z. S. 1858, p. 113, t. x.), from a 

 specimen Dr. Harland received from Hongkong ; but we have many 

 specimens in the British Museum from Natal. 



2. Ciocalypta Tyleri, Bowerbank (P. Z. S. 1873, p. 21, t. iv.). We 

 have several specimens of this " interesting species " in the Museum 

 from Natal ; and Mr. Carter informs me that he can find no differ- 

 ence between it and the crumb-of-bread sponge {Halichonclria 

 panicea) of Ellis, Johnston, and Bowerbank, and it certainly cannot 

 be more than a variety of that species. Dr. Bowerbank says that it 

 is very like the typical species of the genus Ciocalypta. The genus 

 Ciocalypta has always been a puzzle to me. Is that also described 

 from a specimen of Halichonclria, which he says is exceedingly 

 closely allied to the Natal species ? 



If, as we have observed, Haliphysema tubulatum is a Dictyocylin- 

 drus, it is not strange that his Ciocalypta should prove to bo nothing 

 but a common Halichonclria panicea. 



