240 



cated with a very small aviculariuni. The pedal lateral chamber is represented 

 by two (more seldom by three) membranous cavities of somewhat variable form 

 and size. 



Form of colony. Wliile uni- and bi-zooecial internodes seem to alternate 

 regularly everywhere in the principal branches, we may find two bizocecial inter- 

 nodes succeeding each other immediately on the proximal side of the ooecium. 



Of this species I have examined colonies from Port Pliillip and from Port 

 Phillip Heads, Victoria (Miss Jelly). 



Cribricella cribraria Busk. 



Catenicella cribraria Bnsk, Voyage of Rattlesnake, I, pag. 359, Catalogue of Marine 



Polyzoa, Cheilostomata, pag. 9, PI. V, fig. 3 — 4, Challenger, Zoology, 



Vol. X, Part I, pag. 11, fig. 6. 



(PI. XII, figs. 8 a-8 c). 



The zooecia broadly oval. The sternal area with numerous pores, of which 

 those situated in the margin are much larger than those scattered inside. The 

 aperture with a proximal concave margin, from the centre of which issues a 

 sutural line. This line separates two short, plate-sliaped, hollow spines, which 

 are provided with small pores and may be strongly arched. There is a narrow, 

 curved transverse slit on the proximal side of the aperture. 



The lateral chambers. The scapular chamber is everywhere, also on the ad- 

 zocecial side of the daughter-zooecium, developed as a large, compressed avicu- 

 lariuni, the stronglj^ concave frontal surface of which is bounded at both ends 

 by a process. The supra-scapular chamber, which is almost wholly calcified, is 

 long, narrow and provided with a curved terminal part. A very short lateral 

 branch ending in a pore starts from the jyoximal half of its frontal side and its 

 bent proximal end, which can be seen from the basal surface, likewise termin- 

 ates in an uncalcified portion. The infra-scapular and the pedal chambers are 

 well separated, long, narrow and provided with a longitudinal slit. An infra- 

 scapular, adzooecial chamber is wanting in the mother-zooecium. 



The ooecium. The gonozooecium, which is twice as high as the covering 

 kenozooecium, is situated sometimes on a mother-zooecium, sometimes on an in- 

 serted zooecium. The sternal area is somewhat depressed and provided with 

 numerous scattered pores, of which the inner ones are in part larger than on the 

 zooecium. The aperture has an almost straight proximal margin, and there are no 

 hollow spines. Two very narrow lateral chambers with a slit-like opening are 

 found along each lateral margin. The covering kenozooecium has a distal, more 

 strongly arched, indistinctly marked portion and on each side a large, pear-shaped 



