12 n MR. A. W. WATERS ON TITBUCELLARIA : 



TuBucELLAitiA '. its Species and Ovicells. 

 By Arthur Wm. Waters, F.L.S. 



(Plates 15 & 16.) 



Collections made by Cyril Crossland, Esq., from the Red Sea, Zanzibar, and 

 (Jape Verde Islands contain species of Tuhucellaria, and in one from Zanzibar 

 sections have revealed several interesting points concerning the ovicells, about 

 which nothing has been definitely known. It has therefore seemed advisable 

 to deal with this genns at once, instead of waiting for the description of the 

 collections upon which I am now at work. 



The recent species T. cereoides, Ell. & Sol., and T. hirsuta, Lamx., are well 

 known, and d'Orbigny described without figures another as T. fusiformis, to 

 which I am able to add T. sanzibariensis, sp. nov. It will thus be seen that it 

 is but a small genus occurring in the northern and southern temperates and 

 the tropics, and also represented by a few species in the tertiaries of Europe 

 and Australia. 



There has been some uncertainty with regard to the specific names, but this 

 is dealt with under the different species and it is to be hoped that the position 

 will now be clearer. 



It will be best to deal with the ovicell here, as there are various physio- 

 logical facts of considerable importance to be noticed. 



Busk * figured a tubular peristome curved inwards in Tuhucellaria hirsuta, 

 Lamx., but does not seem to have alluded to it. I f figured it in T. cereoides 

 from Australia, and Reuss % mentioned it in fossil cereoides from the Austrian 

 Miocene, and, further, one was figured by me § in fossil Porina papillosa, 

 Reuss. Levinsen || in a most important paper has called these peristomial 

 prolongations " peristomial ooecia," a name which had occurred to me when 

 I w^as working on these ovicells, before recalling Levinsen's designation. 

 Although Levinsen recognised their true nature, he gives no further 

 particulars, but indicates that Porina magnirostris has similar ovicells. In 

 my specimens of P. magnirostris, McG., there is no trace of ovicells, nor does 

 this species seem closely allied to Tidmcellaria in other particulars. 



The ovicell which I figured in the peristome of specimens which I named 

 Porina coronata, Reuss, is structurally allied to that of Tidmcellaria. This, 

 however, may have to be removed from P. coronata. 



* Quart. Journ. Mic. Sc. vol. iii. p. 320, pi. 3. fig. 5, 1885. 

 t Ann. Mag. Nat. Hist. ser. 5, vol. xx. p. 190, pi. 5. fig. 10, 1887. 



X "Foss. Br}', des Oest.-ung. Miociins," Denkschr. math.-naturwissenscli. kais. Akad. der 

 Wissensch. vol. xxxiii. p. 147 (7), 1873. 



§ Quart. Journ. Geol. Soc. vol. xlvii. p. 25, pi. 3. fig. 19, 1891, 



II " Studies on Bryozoa," Vidensk. Medd. fra den Nat. Foren. i Kjobenhavn, 1902. 



