BRYOZOA FROM S.W. VICTORIA, AUSTRALIA. 



313 



use are synonyms. As with other Bryozoa, so in Catenicella, the 

 form of the aperture will have to be considered of primary impor- 

 tance. This Mr. Wilson does not seem to have appreciated ; for 

 only in one case does he mention the shape of the aperture, and, 

 while in some the shape may not be distinguishable, we can hardly 

 suppose that all the twelve are so badly preserved as to have this 

 principal character destroyed. I have recently found two species 

 of Catenicella in the Geological Society's collection from Mount 

 Gambier. It is therefore not impossible that when the figures which 

 Mr. Wilson promises are published, one or two may be found to 

 occur near Geelong and in the present locality. 



One most extremely interesting form — indeed, the most interest- 

 ing specimen in the collection — is Catenicella internodia (fig. 78), 

 consisting of long internodes with a double row of cells, whereas all 

 the Catenicellidse now living have short beaded internodes, consisting 

 of one, two, or even three cells ; and we may find that forms with 

 one or two cells in a node have developed from multicellular nodes, 

 and should then ask, have not all jointed forms adapted themselves 

 from unjointed ones? This and the Mount-Gambier collections 

 furnish unjointed Crisice. In the living fauna of Australia the 

 number of jointed forms is very remarkable ; but already in the 

 European Chalk the number was very considerable. 



The Microporellidse are well represented, and also show that the 

 genus Microporella must be extended ; for we are able to trace rela- 

 tionship from M. violacea, with a round pore, to the v&r.jissa, with an 

 elongate pore (fig. 73) ; then we have M. yarraensis, with two or three 

 denticulated pores in the depression ; and in this way pass on by M. 

 eoscinopora and var. armata, to M. symmetrica (fig. 83). This group, 

 with an area with several large pores, was well represented in the 

 Eocene and Miocene of Europe by M. eoscinopora &c. ; and perhaps 

 as the recent forms are further studied we shall find several living 

 allies ; for Microporella (Eschara) distoma, Busk, from Madeira and, 

 in my collection, from Capri, from 150 metres, must evidently be 

 looked upon as related ; and I find in my specimens from Capri that 

 the pores are stelliform, which seems to be a frequent if not general 

 character in the group, and is of great interest, as showing a corre- 

 lation of characters, and supports the opinion of those who believe 

 that we are now on the track towards a more natural classification. 

 From the above remarks it will be judged that Porellina, Sm., which 

 is separated from the other Microporellidae in consequence of having 

 the pore in a lunate form, is not considered a necessary genus. 



If the comparison is extended a little further we may find that 

 such a form as M. symmetrica (fig. 83) is related to the Cribril- 

 linidaB through such forms as C. terminata (fig. 68). 



In studying both recent and fossil forms I have often been im- 

 pressed with the frequency Avith which open pores are replaced by 

 avicularia, and think that it is a matter worthy of most careful 

 examination ; and, considering that there is reason to believe that 

 avicularia may be only differentiated pores, I enter into the question 

 when speaking of Cribrillina suggerens. 



