REPORT OF THE DIRECTOR I918 1 87 



Anomalina grosserugosa (Gumbel) 



Plate 6, figures 1, 2a, b 



Truncatulina grosserugosa Giimbsl, 1868, Abhandl. baysr 

 A^.cad. Wiss., II, CI., io:65o, pi. ii, fig. 104, a, b 



On slide 5 (X) we find a section of a double-walled, coarsely built 

 and large rotaline foraminiferan in which the cutting has exposed 

 three cha,nibers set on edge. A still better specimen showing four 

 segments cut on edge is seen on slide i and is used for our illustration 

 on plate 6. This is one of the largest rotaline species observed and 

 measures 0.27 mm across the four segments. These seem to be 

 Anomalina grosserugosa (Gumbel) , as they are too 

 large for Pulvinulina and related hyaline types. We tentatively 

 place these specimens under Anomalina, for if they were Nonionina 

 there would be a canal system between the walls as in Rotalia. 

 Since true Rotaliae are present in these cherts we can see no reason 

 why Anomalina should not also be present. The specimen shown 

 on slide 5 (X) measures o.io mm in diameter, but the shell must 

 have been cut near the outer margin as but three segments occur. 



Anomalina grosserugosa is known in late Cretaceous 

 formations but we are not aware that it has hitherto been recognized 

 in Paleozoic formations. 



Genus PULVINULINA Parker & Jones 



It is singular that Pulvinulina should have been recorded in 

 deposits of Lower Cambrian age \ as it is a beautiful example of 

 higher rotaline forms. It is, however, constructed with fewer 

 chambers than most of the related genera, but these vary in number 

 from seven to twenty -six, and the shell wall is without a canal 

 system. It is often prismatic in structure, approaching nummuline 

 character, seen so well in Amphistegina and Nummulites. Brady 

 in his Carboniferous monograph recognizes but one species of this 

 genus, but this type is not present in our cherts. In some of the 

 highest types a faint canal system develops, but it is not distinct 

 as in Rotalia. 



We recognize three species which seem to belong to this genus, 

 and fortunately some of these are cut on edge so as to delineate 

 the convex feature all such forms possess. 



^Ehrenberg, Monats. Preuss. Akad. Wiss. Berlin, 1858, p. 324-27, pi. i. 



