245 



Claviporella pusilla Wilson. 

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

 — — Mac. Gillivray, Mc. Coy, Prodromus ol' the Zoology of 



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

 (I'l. XII, lij^s. 4a-ll). 



The zooecia are [)ear-shaped, very strongly arched and piovided with small, 

 scattered pores. The small sternal area has hut a single, very small fenestra he- 

 sides the larger median one, situated j)roximally to the sutural line, and the two 

 spines, meeting in the latter, have often an inner cavity. The a|)erture has a 

 rather hroad, 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 rohust, spine-like process on either side of the aperture 

 heing the scajjular chandler. 



The lateral chambers. As far as 1 can see on the examined I'ragments the 

 scapular chand)er is everywhere developed into an avicularium with a small, 

 triangular mandihle (fig. 4 g). The chamher itself is of a shorl, thick, robust, 

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

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

 found a small, rudimentary, infra-scapular chamher. 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-zooecium. 



The ooecium. The gonozocvcium is a mother-zoa'cium. The form of its aj)er- 

 lure is similar to that of the gonozorecium in CI. aiirihi, and here too a smaller 

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

 chamber on the adzoa-cial side is not developed as an avicularium and is shaped 

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

 part there is a rudimentary, infra-scapular chamber. The covering zoa?cium, the 

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

 lacks the small i)ore of the sternal area as well as the rudimentary i)edal cham- 

 her. The internode is not completed by Ihe covering zoa'cium any more than in 

 (II. <n'min<tUi. 



Form of colony. In the principal branches uni- and i)i-zo(rcial internodes 

 alternate regularly and rows of single zoo'cia ap|)(ar. 



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

 cia of which had been attacked by alga- and Foraminifera. 



