BEYOZOA FROM ZANZIBAR. 531 



contain polypides and buds, the embryos are only a stage in the 

 life of the goncecia. 



In the present species the two outer rows of zooecia are, in parts 

 of the colony, larger than the rest, forming goncecia with a larger 

 and wider oral aperture, also the pore below it is wider, and a 

 short tongue fi'om the distal end sometimes divides the pore into 

 two. In many sj^ecies of the Adeonidfe where there are gonoecia 

 they occur at the border of the zoarium or near a bifurcation, but 

 apparently in no species are they continuous all along the border. 

 When the zooecia are blind or closed there is often a disc with a 

 central tubule in about the position of the oral aperture. 



In A. platalea there ai-e at the border of the zoarium, besides 

 the large avicularia, very minute ones between the two zocecia, 

 and sometimes the small chamber has a round opening and no 

 mandible. 



Loc. Bass's Straits ; Cape Capricorn ; Victoria, Queensland 

 {3IacG.) ; Port Darwin {Brit. Mus. Coll.) ; China Seas, 82-102 

 fath. (Chall.) ; Thursday Island {Meissner) ; Ye, Burmah Coast 

 (Thorneh/); Basilan, Indian Ocean (d'Orb.). Wasin, Brit. E. 

 Africa, 10 fath. (501, 520) ; Ras Osowamembe, Zanzibar Channel, 

 10 fath. (504) ; Prison Island, Zanzibar Channel, 8 fath. (505) : 

 collected by Crossland. 



Adeonellopsis crosslandi, sp. n. (PI. LXXIII. figs. 1, 2, 6, 7, 

 12-14.) 



This is, in many respects, like A. suhsulcata Smitt, but there 

 seems sufficient reason for separation, for the ridge surrounding 

 the area in siobsulcata is here wanting and the suboral avicularium 

 is directed laterally. 



The zoarium consists of fiat branches (a little over 1 mm. wide 

 and less, than 1 mm. thick) frequently bifurcating and sometimes 

 anastomosing. 



All the zooecia are about the same size, no difference being- 

 discoverable externally in the ovicelligerous zooecia, although in 

 sections zooecia nearly filled by the embryo ai'e found occurring 

 indifterently in any position except in the outer zooecia. The 

 proximal border of the aperture is crenulate and this, as mentioned 

 by Miss Thornely, is the case in suhsulcata ; also the broad median 

 pore is denticulate ; however, in some zooecia, especially those next 

 to the outer row, there is no apparent pore. 



There is a small triangular avicularium immediately below or 

 within the aperture, and often a few of the zooecia near a bifui'ca- 

 tion, and some of the bordering zooecia have also an avicularium 

 at the proximal edge. 



The zooecia at the sides of the zoarium are opposite as, in fact, 

 are all the zooecia, so that the oral apertures on both sides rise to 

 the same height. On the side of the zoarium there are no 

 vicarious avicularia, whereas they occur in A. distoma, A. suh- 

 sulcata, and A. hnperforata. 

 Proc. Zool. See— 1913, No. XXXYI. 36 



