3G0 BULLETIN OF THE 



list of C. B. Adams as had a free open umbilicus and a peculiar nucleus, as 

 described by Carpenter (Mazatlan Shells, p. 237), and one of this sort (V. valca- 

 toides C. B. Adams) was selected as an example of the genus by H. & A. Adams 

 (Gen., I. p. 434, June, 1854), and may be regarded as the type of the genus as 

 revised by the brothers Adams. Of course, if these forms were found eventu- 

 ally to belong to Adeorbis or Cyclostrema, the name Vitrinella would have to 

 fall back upon Ethalia, and the latter would become a synonym of it, for a sub- 

 sequent author could not be permitted to engineer his predecessors' generic 

 names out of existence by appropriating the valid parts for new groups of later 

 names, and leaving the residue to fall into synonymy. But it is probable that 

 Vitrinella, as above constituted, does form a valid group, and we shall so con- 

 sider it, though uncognate species may have been referred to it. 



For present purposes I shall adopt the following arrangement of the others. 



Genus TEINOSTOMA Adams. 



Subgenera Teinostoma s. s. 



Pseudorotella Fischer. 

 Ethalia H. & A. Adams. 

 Dillwynella Dall. 

 Discopsis De Folin. 



In July, 1857, Dr. Paul Fischer proposed the name of Pseudorotella for 

 Teinostoma semistriata Orb. sp., which may be retained as a section for those 

 species having an oval aperture. Parkeria Gabb is a synonym. 



? Genus COCHLIOLEPIS Stimpson. 



In January, 1858, Dr. Stimpson (Proc. Bost. Soc. Nat. Hist., VI. 30S) pro- 

 posed a new genus for a curious little shell found parasitic under the scales of 

 a large annelid (Acoeles lupinus). This little mollusk, with peculiar anatomi- 

 cal characters and a shell like a minute vitreous Sigaretus, is probably allied 

 to Vitrinella, and was named Cocldiolepis parasitica. A second species, larger 

 and fewer whorled, has strong spiral striae like a minute Sigaretus perspectivus, 

 and was named C. striata by Stimpson in his manuscripts. It is about 6.5 mm. 

 in greatest diameter, and 1.5 mm. high. It has two whorls and a globular 

 nucleus almost enveloped above by the last whorl, and a very wide pervious 

 umbilicus. Colonel Jewett collected it at Egmont Key, near Tampa, Florida. 

 The original type of Cochliolepis is found in the South Carolina Post Pliocene, 

 and by an unfortunate error was figured by Holmes as a new species, under the 

 name of Adeorbis nautiliformis. The species figured in his work as Cochlio- 

 lepis parasitica is a probably new species of Vitrinella, which may be named 

 V. Holmesi, and the "Angaria" crassa figured on the same plate appears to be 

 an Ethalia. 



It is certain that Adeorbis does not belong in this vicinity, though the shells 



