245 



Claviporella pusilla Wilson. 

 . Catenicellopsis pusilla Wilson, Quart. Journal Micr. Soc. Victoria, 1880, pag. 64. 

 — — Mac. Gillivray, Mc. Coy, Prodroraus of the Zoology of 



Victoria, decade XI, pag. 29, PI. 107, figs. 1—1 c. 

 (Pi. XII, figs. 4 a-4 f). 



The zooecia are pear-shaped, very strongly arched and provided with small, 

 scattered pores. The small sternal area has but a single, very small fenestra be- 

 sides the larger median one, situated proximally to the sutural line, and the two 

 spines, meeting in the latter, have often an inner cavity. The aperture has a 

 rather broad, rounded sinus, on the distal side of which we find two widely 

 separated, slightly diverging, generally slender, cylindrical spines. Special lateral 

 spines are wanting, the robust, spine-like process on either side of the aperture 

 being the scapular chamber. 



The lateral chambers. As far as I can see on the examined fragments the 

 scapular chamber is everywhere developed into an avicularium with a small, 

 triangular mandible (fig. 4 g). The chamber itself is of a short, thick, robust, 

 cylindrical or conical form and is wholly calcified. A supra-scapular chamber 

 seems to be wanting, and in the proximal part of the avicularian chamber is 

 found a small, rudimentary, infra-scapular chamber. As in the other two species 

 a rudimentary, pedal chamber is present, whereas there is no small chamber on 

 the boundary between the mother- and the daughter-zocecium. 



The ooBcium. The gonozocecium is a mother-zooecium. The form of its aper- 

 ture is similar to that of the gonozocecium in CI. aiirita, and here too a smaller 

 or larger part of the sinus may be covered by the two spines. The scapular 

 chamber on the adzocecial side is not developed as an avicularium and is shaped 

 like a strong, somewhat bent spine of the length of the aperture. At its proximal 

 part there is a rudimentary, infra-scapular chamber. The covering zooecium, the 

 arched, covering part of which is provided with a number of scattered pores, 

 lacks the small pore of the sternal area as well as the rudimentary pedal cham- 

 ber. The internode is not completed by the covering zooecium any more than in 

 CI. geminata. 



Form of colony. In the principal branches uni- and bi-zocecial internodes 

 alternate regularly and rows of single zooecia appear. 



Of this species I have examined some dead colonies from Victoria, most zooe- 

 cia of which had been attacked by algse and Foraminifera, 



