BRYOZOA PROM ZANZIBAR. 479 



SCRUPOCELLARIA WASINENSIS, Sp. n, (PI. LXVIII. figs. 9, 10 ; 



PI. LXIX. tigs. 17-19.) 



Zoaiium usually with 5 or 7 zocecia in an internode. Zooecia 

 wide, with the round area occupying more than half the length 

 of the zocecium ; at the distal end there are three exterior spines 

 and one interior; the anterior avicularia are medium-sized, 

 raised, tubular, with a narrow triangular mandible ; the latei-al 

 avicularin. a.re very small ; the vibracular, together with the i-adi- 

 cular chamber, is about half the length of a zooecium, the delicate 

 vibracular setse are smooth and slightly longer than a zooecium ; 

 the vibracular chamber is separated near the base from the 

 radicular chamber, and the distal end is contracted. There is 

 one vibraculum at a bifurcation. A few large lateral avicularia 

 have been seen which are divided at the end, and the mandible 

 is forked like that of >S. serrata Waters *. 



The globular ovicell has numerous pores. 



The radicles sometimes pass from one branch to another, as in 

 Caberea retiformis Sm. 



There are about 16 tentacles. 



The ovaries containing many ova are at the distal end, while 

 testes in the same zooecia are at the proximal end. The ovaria 

 in Scrxifocellaria contain several ova, but the ovaria in this 

 species are peculiar, as there are at first a number of large homo- 

 geneous cells of which usually only one or two show any nucleus 

 (PL LXIX. fig. 19). The ovaria at this stage show no follicular 

 wall, but at a later stage, when the yolk-mass of an ovum has 

 become very large, then the follicular wall is distinct. 



In this species, as in other Scrupocellai-ice, a large ovum passes 

 into the ovicell, whereas in Bugula the ovaria instead of being 

 distal are proximal, and a small ovum in a very early stage passes 

 into the ovicell f. The ovarian cells, which are frequently far 

 apart, are often surrounded by a protoplasmic netwoik which 

 passes up to the rosette-plate of the next zooecium (figs. 18, 19). 

 This species is of about the same size as aS'. mansueta Waters, but 

 has four distal spines and a much smaller vibraculum, with setie 

 more delicate, and about half to one- third the length of the latter 

 form. The large lateral avicularia are known in S. varians 

 Hincks, S. serrata Waters, and S. ohtecta Haswell, but apparently 

 are only the ordinaiy avicularia more developed. 



Log. Wasin, Brit. East Africa, 20 fath. (522), collected by 

 Orossland. 



Canda retiformis Pourtales. (PI. LXIX. figs. 1, 2, 6.) 

 Cancla retiformis Pourtales, Bull. Mus. Comp. Zool. Harvard 

 Coll., I., No. 6, p. 110 (1867) ; Philipps, "Rep. on Polyzoa," Willey, 



* " Bryozoa of Sudanese Red Sea," Journ. Linn. Soc, Zool. vol. sxxi. p. 133, pi. x. 

 fig. 11. 



f In Bugula there are two small ova in each ovarium, occasionally three, or even 

 four, small ones; however, in B. niurrayana Johnst., now called Dendroheania 

 by Levinsen, the ovarium is distal, and the ova in the ovarium grow to a large size, 

 so that the material ditferences in the ovaria would alone suggest that murrai/ana 

 does not belong to the same genus as B. avictdaris, etc. 



