14 MR. A. W. WATERS ON THE MARINE 



sufficient ground for separating T. novce-hollandice from Rozieri. Further 

 cleaning of one of my specimens, sent by Haswell, revealed an avicularium 

 similar to the one figured by Levinsen. With ovicells and avicularia 

 unknown, it was difficult to be certain of the specific identity. 



Levinsen's studies of the spicules in Thalamoporella are most important, 

 but we do not know much as to the positions in which they occur, nor as to 

 their object. In T. Rozieri from both the Red Sea and Cape Verde Islands 

 there are two bundles of the long straight spicules starting from near the 

 opercula and passing diagonally by the walls of the opesiules to the lateral 

 walls, near the basal wall (PI. 4. fig. 9). The long straight spicules are 

 mostly free in the zooecium, and at one time I wondered whether they were 

 arranged in this way by the polypide passing in and out of the zooecium, but 

 these bundles occur in very young zooecia before any calcareous frontal wall 

 or operculum is formed. There are on, or in, the membranes spicules which 

 Levinsen called curves, but in the sponges they would be called sigmas or 

 arcuate spicules, and perhaps it would be well to speak of them as sigmas. 

 These are remarkably abundant in Th. Jervoisi, H., and T. mamillaris, 

 Lamx., from various localities. A specimen of Jervoisi, from Queensland, 

 in my collection, has these spicules in great abundance in both the basal and 

 frontal membranes, and at the growing end where the beginning of the 

 lateral wall is only just indicated, on the supporting seaweed, these sigmas 

 are massed in abundance. 



Dr. Alice Robertson considers that her specimens, from La Jolla, California, 

 are var. indica, Hincks, which hardly seems to differ from the type, others 

 from San Pedro are articulated, and I expect this will ultimately be generically 

 separated. Osburn considered his specimens from Tortugas Island were var. 

 labiata, Levinsen, but the difference of the avicularium as figured by Levinsen 

 may suffice to make labiata a genus. I do not consider that the presence or 

 absence of avicularia is of first class importance, as often some colonies of 

 Thalamoporella may have them while others are without ; on the contrary, 

 the type of avicularium and mandible is of material importance. 



Localities, additional. California, few fath. : San Diego (Robertson), 

 Florida, Jamaica, Tortugas Bay ; Cape Verde Islands, St. Vincent Harbour, 

 10 fath., collected by Crossland. 



Schizoporella unicornis (Johyiston), Pergens. (Plate 2. figs. 14-17, 22.) 

 For synonyms see Waters, " Bryozoa of the Sudanese Red Sea," Journ. Linn. Soc, 

 Zool. vol. xxxi. (1909) p. 143, pi. 12. figs. 12, 13, and add :— 



Nordgaard, Die Bry. des West Norweg. p. 86 (1903) ; Hydrog. & Biol. Invert, in 

 Norwegian Fiords, p. 165, pi. 5. figs. 23-25, 27 (1905) ; Calvet, ExpeU Sc. du < Travailleur ' 

 et du 'Talisman,' vol. viii. (1907) p. 417 ; Norman, " Polyzoa of Madeira and neighbouring 

 Islands," Journ. Linn. Soc, Zool. vol. xxx. (1909) p. 303 ; Osburn, " Bry. of Woods Hole 

 Region," Bull. Bur. of Fisheries, vol. xxx. (1912) p. 236, pi. 25. fig. 48, pi. 30. fig. 91 ; " Bry. 

 of the Tortugas Islands, Florida," Publ. 182, Carnegie Inst, of Washington, p. 205 (1914) ; 

 Waters, " Bry. from Zanzibar," Proc, Zool. Soc. 1913, p, 501, 



