REPORT OF THE DIRECTOR I918 159 



the shape of the ultimate chambers in all these related conical Textu- 

 lariae, but not a sufficient difference to distinguish each species. 

 In existing types T. trochus measures a distance across almost 

 as great as the length of the shell, but this does not hold true for all 

 fossil forms. In our example the width of the anterior end is 0.23, 

 as against a length of 0.35 mm. 



Genus VALVULINA d'Orbigny 



The genus Valvulina has hitherto been supposed to be limited 

 to the Carboniferous and succeeding horizons. Prof. H. B. Brady 

 identified many forms of this triserial foraminiferan in the Carboni- 

 ferous of Europe ; Mr Chapman in the Portland Oolite (Stramberg 

 limestone) ; and it is an unusual type in existing oceans. On slide i 

 is a very large, almost circular, thick-walled foraminiferan which I 

 think must belong to this genus but we can not of course identify the 

 species as we have no vertical section of the same fossil. 



Valvulina sp. 



Plate I, figures 1 1 and 12 (another species) 



The form identified doubtfully as Valvulina (slide i ; see figure 1 1) 

 is very large, measuring 0.42 mm across its nearly circular test. There 

 are but five transverse segments present, and each is separated by 

 heavy, thick, arched septa becoming still more massive at the peri- 

 phery. We know of no rotaline form so large and massive which 

 could furnish so circular a section. Valvulina paleotro- 

 c h u s (Ehrenberg) described by Professor Brady in his Carboniferous 

 Monograph would closely approximate this type. Valvulina 

 allomorphinoides Reuss would show the same number of 

 segments, but the figured form of Reuss is not round and its margin 

 is slightly limbate, as in figure 12. We do not seem to find very 

 many species identical with the European Carboniferous; and such 

 types as would most certainly occur if we had Carboniferous Foram- 

 inifera, like Fusiilina and Endothyra, are entirely lacking. However, 

 we provisionally place this specimen under Valvulina and also the 

 specimen shown in figure 12, but they can not be further identified 

 until other sections reveal the lateral form. It is strange that if this 

 genus were common we do not find other types cut so that they reveal 

 its true character. Possible small types are seen also on slides 4 

 and 5. 



