BRYOZOA FROM ZANZIBAR. 



491 



line on the dorsal surface with the zocecia on each side. The 

 front wall has a minute pore on each side below the oral aperture 

 (fig. 13), but these are only seen in Eau de Javelle preparations, 

 and in the same way the long slit-like pore on the one side i^> 

 scarcely seen so long as the membrane covei^s the walls. The 

 muscles passing through this slit are wide, and are attached to a 



Diplodidymia complicata Reuss. 



A. Sliowiug small sacs hanging from the opercular region, and in each an ovum 

 grows (oy.). At y. there seems as yet no ovum iu the small sac; w., the 

 muscles of the opesium. X 50. 



B. Section showing an ovum in the small sac. X 250. 



C. Section in which the ovum has segmented and a blasluta is formed. X 250. 



chitinous thickening or sclerite on the front membrane, and are 

 partly protected by a calcareous wall. Thei-e are two rosette- 

 plates in the entire lateral wall. On the avicularian chamber 

 there is a concave pit with a central perforation, no doubt indi- 

 cating that radicles can be given off from this pit, and thereby 



