227 



itself is provided with two long but also broad and close bells of ])oies, while 

 the calcified portions are connected willi tlie ocrciuni by a great many strong, 

 cylindrical or conical spinous processes springing from the latter. A number of 

 these [)rocesses outside tlie calcified portions serve to support the membranous 

 part of the covering kenozooecium. In the approximate centre of the basal region 

 we find the starting point of a small, meml)ranous, triangular chamber, which is 

 ])rovided with a series of chitinous denticles along each lateral margin, and which 

 communicates with the oa^cium through a triangular basal surface with two 

 symmetrically arranged groups of o — 7 uniporous rosette-plates. A shoil, low, 

 median, calcareous ridge springs from the |)roximal side of the basal surface and 

 possibly originates from a median separating wall. 



Scuticella ventricosa lUisk. 

 Catenicella ventricosa Busk, Voyage of Rattlesnake, I, pag. 357, t. 1, fig. 1, 



Catalogue of Marine Polyzoa, Cheilostomata, pag. 7, PI. II, figs. 1, 2. 

 (PI. XX, figs. 5 a-.-) c (;i), PI. XI, tigs. 6a-61j). 



The zocEcia hexagonally oval with an aperture bounded by a slighlly concave, 

 proximal margin, which has an extremely short sutural line centrally. The 

 slernal area is provided with 5—7 fenestra; converging at an acute angle, and 

 the inner ciyplocyst lamina is of a triangularly pointed form and may allaiii 

 about half the length of the sternal area. 



The lateral chambers. Except on the adzoa-cial side of the daughter-zon'cium 

 in a bizoo'cial segmeni, the scapular clunnbcr is everywhere developed as an 

 avicularium with a small, oval mandible, and the supra-scapular chamber, the 

 wall of which is only calcified in its outermost part distally to the avicularium, 

 may end in a shorter or larger, ascending, pointed i)ortion. Proximally to the 

 avicularium we find an oval infra-scapular and a very long, somewhat broader, 

 pedally and more frontally directed cluunber, which occupies about fwo-lhirds 

 of the whole lenglh of the zoa'cium. It is separated from the infra-scapular 

 chamber by a horizontal or somewhat obli(|ue wall, and along its centre provided 

 with a longitudinal row of 5 — 10 rosette-plates. Finally we find in the bizocrcial 

 segment on the boundary between the mollu'r- and the daughter-zoa'ciuni n long, 

 narrow, distally directed cavity (PI. XX, fig. 5 b, m. Ill), which almost reaches 

 the i)edal chamber of the mother-zorecium proximally, and which communicates 

 with the mother-zoo'cium through a row of 4 rosette-plates. It must be regarded 

 as the adzoa'cial, inlVa-scapular chamber of the mother-zoa-cium. 



The ooecium (PI. XI, figs. Ba — 6 b). The gonozooecium, which is about twice 

 the length of the covering kenozoa-cium, is most often situated on the molher- 



1.-.* 



