239 



Cribricella rufa Mac Gillivray. 

 Catenicella rufa M. Gillivr., Transact. Royal Soc. of Victoria 1868, 



Vol. IX, pag. 126. 

 (PI. XII, figs. 7 a-7 f). 



The , zooBcia are elongated, quadrangularly oval, and the sternal area is pro- 

 vided with numerous scattered pores, of which the outermost are not much larger 

 than those situated further in. The aperture has a proximal concave margin with 

 a small, rounded sinus centrally. 



The lateral chambers. The scapular chamber is in most zooecia developed 

 as a generally rather small, frontally directed avicularium, which never appears 

 on the adzocecial side of the daughter-zoceeium. It is usually wanling on the 

 inner side of the single zooecia, which occur in rows and may spring both from 

 a mother- and from a daughter-zoceeium, but in the latter case the opposite avi- 

 cularium is often large. Of the other lateral chambers we see from the frontal 

 surface only a part of the supra-scapular one, which has a membranous roof 

 but a projecting calcified outer wall. The long, narrow infra-scapular chamber 

 passing from the outer side of the avicularium obliquely towards the basal surface 

 bends again more or less far down the latter surface and is at its terminal 

 part almost parallel with the likewise long, narrow pedal chamber, which 

 runs along the lateral margin of the zocecium. The mother-zooecium has a long, 

 infra-scapular, adzocecial chamber. 



The ooecium. The gonozocecium, which is somewhat shorter than the covei-- 

 ing kenozooecium and situated on a mother-zocEcium, is of the same length but 

 twice- the breadth of the zooecia, and the structure of the sternal area is similar 

 to that of the latter. Its wide aperture has a broad, but indistinctly marked sinus, 

 on the proximal side of which a short, broadly rounded, inner cryptocyst plate 

 is seen. Along each lateral margin we find a long, narrow, pedal chamber, bas- 

 ally to which there is a shorter, somewhat curved one, and the chambers corre- 

 spond to those of the distal group. The large covering kenozooecium is on its 

 frontal surface provided with numerous, scattered, rather large pores, and the 

 distal group of lateral chambers is generally represented on either side by an 

 oblong, mostly membranous cavity, in which we may distinguish between a 

 shorter and wider distal part, which can be seen from the frontal surface, and 

 a longer, more narrow, somewhat curved part, which reaches halfway down the 

 basal surface. The projecting wider part, which is often conical, may have more 

 or less strongly calcified walls and often be provided with but a narrow, slit-like 

 opening. In a single case it was only present on one side and then communi- 



