BUTTON : WEST INDIAN CYPR.'EID.T'.. 255 



spots, as these characters are usually much less marked and are some- 

 times entirely lacking. (See note on C. cervus, postea). 



4. — C. exanthema var. cervinetta Kiener. 35 to 92 mm. 

 Panama region, south to Ecuador and Galapagos Islands. 



This form has the small, frequent spots of C. cervus, but is usually 

 greyish on the sides of the base, and shows the four cross-bands well 

 marked. It is peculiar to the Panama region in Pacific waters, and 

 varies in colouring between the Kiener figure (pi. 6, fig. i) and that of 

 Sowerby (no. 181). The shape is flatter than the type and more 

 tapering at the ends. 



5. — C. isabella-mexicana Stearns {Proc. U.S. Nat. Mus., 1893, 

 p. 348). 41 mm. Clipperton Island and Tres Marias Islands (off 

 W. Mexican coast). Figured by Sowerby (fig. 18, not fig. 258) as 

 C. coiitroversa Gray, an unpublished species. This very beautiful 

 shell, an extreme form of the Isabella group, is also said, on doubtful 

 authority, to have been found off the Mexican mainland. I have had 

 it only from Clipperton Island. 



6. — C. nigropunctata Gray. 35 mm. Ecuador and Galapagos 

 Islands. 



7. — C. punctulata Gray. 32 mm. Gulf of California to Panama. 

 8. — C. SOwerbyi Kiener. 51 mm. Lower California to Peru. 

 9. — C. spadicea Swn. 53 mm. Southern California. 

 10. — Pustularia pustulata Lam. 23 mm. Gulf of California 

 to Panama. 



II.— Trivia californica Gray. 12 mm. Central California to 

 Gulf of California. 



12. — T. fusca Gray. 10 mm. ? Galapagos Islands (to Gulf of 

 California ?). 



There has evidently been some confusion as to this species among 

 the monographers. The type from Galapagos Islands was described 

 as " dark-brown, sub-globular, with a pale dorsal streak, ribs few and 

 short ;"^ and it is so figured by Reeve (no. 134, from the Gaskoin 

 specimens) ; while it is figured in the Sowerby monograph as a pink, 

 elongated shell with delicate ribs, although described as " smoky- 

 brown throughout" (no. 72). Dr. Carpenter notes that while the 

 specimens of T. fusca and also of T. rubescens from the Cuming col- 

 lection seem to be only extreme varieties of T. sanguinea, those in the 

 Gaskoin collection appear to be distinct.^ The observations of Dr. 

 Carpenter and of Mr. Sowerby (note to no. 175) relating to the close 

 afifinity of T. fusca to T. sanguinea, appear to be based upon compari- 

 son of specimens all from the West American mainland; and specimens 



Gray, "Descr. Cat. Cyp.," p. 15. 

 "Cat^l. Maz.itlan Shells," p. 378, note. 



