244 



down to an oval pore, and on either side of the suture we generally find an 

 inner cavity belonging to the two short spines, which meet in the latter. 



The lateral chambers. The scapular chamber, which in contrast to that in the 

 preceding species, has no beaked hook, is not everywhere developed as an avicu- 

 larium and is often absent on the one side of a single zooecium as well as of a 

 bizooecial internode. While the three distal lateral chambers together form a body 

 of a shape somewhat similar to that in the foregoing species, the extent of the 

 three chambers separately is different, the scapular chamber being dilated both 

 distally and proximally at the expense of the two other chambers, and the sinus, 

 which in CI. geminata is formed between the scapular and the infra-scapular 

 chamber, is here formed by the former only, the septum between the two cham- 

 bers having retreated much farther proximally. The supra-scapular chamber is 

 separated from the scapular by an angulated septum and has a fissure in its roof. 

 It is an extremely small, triangular or quadrangular cavity, which together with 

 the distal part of the scapular chamber forms a rounded process, the form and 

 position of which reminds one of the distal spines. The infra-scapular chamber 

 is generally triangular and wholly calcified with exception of a small frontal 

 pore. The pedal chamber appears in the same way as in the foregoing species. 

 This may also be said of the above-mentioned chamber on the bizooecial 

 internode. 



The ooecium. The gonozooecium is a single zooecium, and the covering keno- 

 zooecium is of the length of the gonozooecium and has a depression along the 

 centre of the frontal surface, which is provided with a number of widely scat- 

 tered pores. The aperture, which is provided with two distally converging, arch- 

 shaped lateral margins, has a broad, trapeziformly rounded sinus, the proximal 

 part of which is covered by the spines whith meet in the sutural line. On either 

 side of the ajjerture we find a distally directed, strong, conical, lateral spine of 

 the length of the aperture, and outside this on either side a single, rounded quad- 

 rangular, lateral chamber with a small rounded pore. 



Form of colony, Uni- and bi-zooecial internodes alternate, bvit in such a way 

 that two bizooecial internodes succeed each other rather frequently. The single 

 zooecia may spring from the daughter-zooecia in rows of up to 5. They are 

 sometimes on the outer side provided with an avicularium, which may exceed 

 the zooecium in size, and such an enormous avicularium is found especially in 

 a form from Akaroa (New Zealand). 



Of this species I have examined colonies from Port Phillip, Auckland, Cape 

 Wilson and New Zealand. 



