T'wu New Species of Bryozuu. 113 



Ooecia (?) 



Type in the National Museum Collection. 



The specimens available do not exceed about half an inch in 

 height. In some instances the branches spring from the sides of single 

 zooecia, and there may even be one on each side. This is the charac- 

 ter on which Wilson founded the genus Catenicellopsis^ but it was not 

 deemed valid by MacGillivray, who mentions having met vv^ith the 

 same character in Claviporella. It is only in a few of the proximal 

 internodes in one of these specimens that it occurs; higher up the 

 typical mode of branching is constant. 



There are usually four obtuse processes, as in C. aurita. The 

 avicularia are most commonly unequal, but not differing otherwise; 

 sometimes the inequality is considerable, but there are not in these 

 specimens any of the gigantic forms sometimes found in C. aurita. 



The ornamentation of the zcoecium affords a ready means of dis- 

 tinguishing the species from its allies. In place of the large elliptic 

 pore of C. aurita we have here a minute pseudo-pore, often quite indis- 

 tinct, and the broad band surrounding the pore is here represented 

 by a less distinct circular area. The fenestrae in C. aurita are mostly 

 four or five, and somewhat irregular; in our species there are almost 

 invariably three, regularly placed, and though so minute, both the 

 fenestrae and their fissures are sharply defined. This character also 

 distinguishes the species from C. imperforata and C. pulchra, which 

 latter species, moreover, has an oval central pore and narrower 

 zooecia. 



Large circular cavities behind the zooecia are extremely nume- 

 rous, indicating where tendrils have been detached. The cavities are 

 inside the zooecium, and the tendrils have been broken off flush with 

 the surface, only one remaining. If they all existed at once some of 

 the branches must have fairly bristled with them, but being so brittle 

 it is likely that as new zooecia were produced the tendrils fell from 

 the older ones. In some cases two had existed on a single zooecium. 



EXPLANATION OF PLATE VIII. 



Fig. la Catenicella mattlieivsi x 30. 



-, lb „ back. 



,, Ic „ between crossed nicols. 



M Id „ Ooecium. 



„ le „ Avicularium x 400. 



,, If ,, Decalcified x 75. 



,, 2a Claviporella goldsteini, x 30. 



„ 2b „ back. 



„ 2c „ X 75. 



END OF VOLUME XXXV., PART I. 



[Published 7th December, 1922]. 



