ART. 4 CAMBRIAN CONCHOSTRACA — ULRICH AND BASSLER 103 



sculpture of the surface being like the dorsal side of a tube of that 

 genus. The shell is about 9 mm. long and 4 mm. wide. (Matthew, 

 1899.) 



The type specimen of this species is apparently lost for it is not 

 present in any of the Canadian collections. As no other examples 

 are known to us, the position of the species can not now be deter- 

 mined. The illustration is probably not that of a pelecypod, but pos- 

 sibly represents a worn Hyolithes. 



Occurrence. — Lower Cambrian (Etcheminian) : Newfoundland. 



PRIMITIA SIMPLEX LLOYDIANA Jones 



Priviilia simplex var. lloydiana Jones, Ann. Mag. Nat. Hist., ser. 5, vol. 8, 1881, 

 p. 348, pi. 20, fig. 2. 



This supposed Cambrian variety of an Ordovician species can not 

 be recognized with present mformation. 



Occurrence. — Cambrian: St. eJohn's, Newfoundland. 



PRIMITIA SIMPLEX MILNEANA Jones 



Primitia simplex var. milneana Jones, Ann. Mag. Nat. Hist., ser. 5, vol. 8, 1881, 

 p. 348, pi. 20, fig. 3. 



Not recognizable without further study of the types or topotypes. 

 Occurrence. — Cambrian: St. John's, Newfoundland. 



PRIMITIA SIMPLEX SANCTOJOHANNESIANA Jones 



Primitia simplex var. sandojohannesiana Jones, Ann. Mag. Nat. Hist., ser. 5, 

 vol. 8, 1881, p. 348, pi. 20, fig. 1. 



Like the above, not recognizable. 



Occurrence. — Cambrian: St. John's, Newfoundland. 



BIBLIOGRAPHY 

 Barrande, J. 



1872. Silurian System du Centre Boheme, vol. 1, Suppl. {Beyrichia angelini, 

 etc.). 

 Bassler, R. S. (See Zittel, Karl A. Von.) 

 Burr, H. T. 



1900. A new Lower Cambrian Fauna from eastern Massachusetts. Amer- 

 ican Geologist, vol. 25, pp. 41-50. (Leperditia cf. L. solitaria 

 Barrande.) 

 Chapman, Frederick. 



1918. Ostracoda from the Upper Cambrian limestone of South Australia, 

 etc. Proc. Roy. Society Victoria, new ser., vol. 31, pt. 1, pp. 108- 

 174, pis. 9, 10. (Leperditia tatei, new species, L. capsella, new 

 species, Isochilina sweeli, new species), all resembling genera of 

 Conchostraca.) 



