1915.] NATURAL SCIENCES OF PHILADELPHIA. 25 



NOTES ON THE SEMELID^ OF THE WEST COAST OF AMERICA, INCLUDING 



SOME NEW SPECIES. 



BY WILLIAM H. DALL. 



In revising the Pacific Coast species in the National Collection, 

 considerable confusion was fouird, due in part to the habit of Dr. 

 Carpenter (who originally named the collection) of trusting to the 

 specimens in the collection of Professor C. B. Adams rather than to 

 the diagnoses of that careful author. The specimens in that collec- 

 tion, due to several causes (especially the fact that they were kept 

 loose in trays and not numbered), have in some cases since Professor 

 Adams' death become transposed or mixed, so that, without careful 

 reference to the text, errors of identification were likely to occur. 



Furthermore, the collection of the National Museum since Car- 

 penter's time has been greatly enlarged, and the better and more 

 numerous specimens from a much wider geographical range afford 

 an opportunity for study not available to Dr. Carpenter. 



Semele decisa Conrad, 1837. 



San Pedro to San Diego, California. (Coll. U. S. N. Mus.) 



This species is also reported from Mazatlan and Tagus Cove, 



Galapagos Islands, but I am not able to confirm these localities. 



Semele solida Gray, 1828. 



Peru and Chile. (Coll. U. S. N. Mus.) 



This is also doubtfully reported from the Galapagos Islands. It 

 is the crocea of Gould, 1850, and the orbicularis of Hupe, 1854. 



Semele corrugata Sowerby, 1832. 



Not of C. B. Adams, 1852; and probably the californica of A. 

 Adams, 1853. 



Magdalena Bay, Lower California, to Iquique, Peru. (Coll. 

 U. S. N. Mus.) 



It is possibly only a variety of the preceding or the following species. 

 Semele flavescens Gould, 1851. 



Cape St. Lucas to Callao, Peru. (Coll. U. S. N. Mus.) 



This is the proxima of C. B. Adams, 1852, and the flavicans of 

 Carpenter (1857, lapsus) as of Gould. 

 Semele striosa C. B. Adams, 1852. 



Not of Carpenter, 1857. 



Catalina Island, California, to Panama. (Coll. U. S. N. Mus.) 



