BRYOZOA FROM ZANZIBAR. 511 



of tlie peristome, which fi^equently extends beyond it as a com- 

 plete tube, and the ovicell has an ai'ea which is flat or slightly 

 rounded and is surrounded by a ridge, while at each corner 

 inside the ridge there is a pit. It seems justifiable to call the 

 part surrounded by the ridge an area, bvit if there is any 

 objection to this it might be called a tabula. In this case the 

 " calcareous base" is very slightly developed and might be over- 

 looked, and except that the Guernsey specimen is slightly 

 granular or rather nodulated there is but little difference 

 between it and Lagenipora lucida Hincks from Madeira, except 

 that L. lucida has pores round the area as figured b}^ me *, but 

 I have not the opportunity of now comparing any L. lucida 

 having ovicells. 



Now in Lagenipora nitens MacG. from Port Phillip Heads, 

 which I considei^ed only a variety of lucida, the ovicell is just 

 the same shape and in the same position, while close to the ridge 

 of the area there is a I'ow of pores ; also L. boryii And. from the 

 Mediterranean has a row of pores in the same place, whereas in 

 L.rota MacG. and some other species there are radiating grooves. 

 An Australian species of Lagenipora has the area evenly perforated 

 all over. The pores or pits of L. socialis, though difficult to 

 ti-ace, are no doubt small and close to the edge. When I first 

 thought I saw pores it was puzzling not to find a complete row, 

 and there was a doubt whether they might only result from 

 accidental damage, but no doubt the explanation is that there is 

 only one at each corner. There must be something wrong if 

 Lagenipora socialis and L. lucida are placed in dififerent genera. 



Loc. Victoria (3IacG.). Wasin, Brit. East Africa, 10 fath, 

 (507), collected by Crossland. 



Haswellia australiensis Haswell. 



Myriozoum australiense Haswell, Proc. Linn. Soc. N.S. Wales 

 vol. V. pt. 1, p. 43, pi. iii. figs. 9-11 (1880). 



HasroelUa australiensis Busk, "Polyzoa," Zool. Chall. Exp. vol. x. 

 pt. XXX. p. 172, pi. xxiv. fig. 9 (1884); Kirkpatrick, Proc. Roy. 

 Dublin Soc. vol. vi. p. 612 (1890); Meissner, M., aus Semon 

 "Zool. Forsch. Reisen in Australien und Malay," Jena. Denkschr. 

 vol. viii. p. 731 (1902) ; Levinsen, Morph. & Syst. Studies of the 

 Cheil. Bryozoa, p. 297, pi. xvi. figs. 2 a-2 b (1909). 



Porina coronata var. lahrosa Waters, Zool. Chall. Exp. vol. xxxi. 

 pt. Ixxix. p. 32 (1889). 



Levinsen places this in Myriozoidfe f, but it seems somewhat 

 doubtful whether the genera grouped together by Levinsen will 

 i-emain in the same family (see p. 520). 



The series of zocecia in H. australiensis are all on the same 

 horizon, and usually at the beginning of each branch there are 

 six zooecia in a whorl, there is then another whorl with six, then 

 one with eight when a bifurcation takes place, and then again 



* Journ. R. Micr. Soc. 1899, p. 13, pi. iii. figs. 25, 27,30 (1899). 

 t Loc. cit., see page 296. 



