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itself is provided with two long but also broad and close belts of pores, while 

 the calcified portions are connected with the ooecium by a great many strong, 

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

 these processes outside the 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, membranous, triangular chamber, which is 

 provided with a series of chitinous denticles along each lateral margin, and wliich 

 communicates with the ooecium through a triangular basal surface with two 

 symmetrically arranged groups of 5—7 uniporous rosette-plates. A short, low, 

 median, calcareous ridge springs from the proximal side of the basal surface and 

 possibly originates from a median separating wall. 



Scuticella ventricosa Busk. 

 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-5 c (a), PI. XI, figs. 6 a-6 b). 



The zooecia hexagonally oval with an aperture bounded by a slightly concave, 

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

 sternal area is provided with 5—7 fenestrse converging at an acute angle, and 

 the inner cryptocyst lamina is of a triangularly pointed form and may attain 

 about half the length of the sternal area. 



The lateral chambers. Except on the adzooecial side of the daughter-zooecium 

 in a bizocecial segment, the scapular chamber 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 portion. Proximally to the 

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

 pedally and more frontally directed chamber, which occupies about two-thirds 

 of the whole length of the zooecium. It is separated from the infra-scapular 

 chamber by a horizontal or somewhat oblique wall, and along its centre provided 

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

 segment on the boundary between the mother- and the daughter-zooecium a long, 

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

 the pedal chamber of the mother-zooecium proximally, and which communicates 

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

 as the adzooecial, infra-scapular chamber of the mother-zooecium. 



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

 the length of the covering kenozooecium, is most often situated on the mother- 



15* 



