AET. 6 FOEAMINIFERA: POLYMORPHINIDAE^ — CUSHMAN AND OZAWA / 



Chapman described two species of Polymorphina, P. seminis, and P. 

 archaica from the Middle Devonian of Eifel in Germany. They 

 resemble Globulina in their general outline. From the phylogenetic 

 consideration of the family, we doubt if they be true Globulina. No 

 other authors have noted the occurrence of the Polymorphinidae in 

 the Paleozoic rocks. 



In the Mesozoic the Polymorphinidae became gradually frequent 

 although most Triassic species are doubtful. Guttulina (f) raibliana, 

 described by Gtimbel from the Upper Triassic of Austria, judged from 

 the figure, surely belongs to the Polymorphinidae. It resembles 

 Guttulina, but the chambers seem to be arranged in a spiral series, as 

 in many of the more primitive Jurassic species. 



With the beginning of the Jurassic the Polymorphinidae are of 

 rather frequent occurrence, and more than 50 species are recorded from 

 various Jurassic deposits in Europe. Some of them are identified 

 with Tertiary or Recent species, such as P. burdigalensis , P. compressa 

 etc., but most of them are known only from the Jurassic. Terquem 

 described most of the Jurassic species from the Oolite and the Lias in 

 France. These Jurassic species are very important for a study of 

 the earlier forms of the Polymorphinidae and its relationships with 

 the Lagenidae. Terquem 's figures are probably not drawn well, and 

 no end view showing the arrangement of chambers is given. Ozawa 

 tried to examine Terquem's original specimens in Paris, but it was 

 almost impossible because they are not in good order. Therefore the 

 following discussion of the arrangement of chambers of Jurassic 

 species is according to Terquem's figures with the aid obtained from 

 a study of our Jurassic specimens found in England. 



Among Terquem's species, Polymorphina bilocularis is a two- 

 chambered fusiform species and is very similar to Vaginulina, but the 

 second chamber more or less deviates from the coiled position of 

 Vaginulina, and is in a spiral position. 



Schwager's Globulina secale (1865), in its external appearance, is 

 almost identical with P. bilocularis (1864), but it has numerous cham- 

 bers, most of which are entirely embraced by the last two chambers 

 and are not visible from the exterior. From Schwager's description 

 and figures alone it is almost impossible to determine whether or not 

 the species really belongs to the Polymorphinidae. 



Polymorphina intorta Terquem, P. nitidiuscula Terquem, and 

 P. obliqua Terquem, judging from their figures, may represent inter- 

 mediate stages between coiled Vaginulina and spiral Polymorphini- 

 dae. Their successive chambers are added in planes less than 

 90° apart from one another. P. sacculus Terquem is a rather inter- 

 esting species, having three chambers, arranged evidently in a spiral 

 series. Terquem's species Polymorphina triloba, P. breoni, P. poly- 

 gona, P. ovula, and P. avena have more than two chambers arranged 



