^'^IHW^''] PROCEEDINGS OF THE NATIONAL MUSEUM. 345 



iiig similar general characters. Some examples of brunneostoma are 

 more robust than others and vary in the elevation of the spire. 



Dimensions: Length of largest, 10 uiilliraeters; breadth, miUi- 

 meters; an iiiterniediate example measures 15 millimeters in length 

 and S inillinieters in breadth. This last is, however, much above the 

 average in size. 



Haijitat. — Gulf of California, near the mouth of the Colorado River 

 (Mus. No. 37239); also at Guaymas, on the easterly shore (No. 23721, 

 5o951), where numerous examjdes were collected by Dr. Edward Palmer. 



Family MIIKICID^. 

 Subfamily Murioin^. 



(ieiiUH MUREX Liiiii.-. 

 Subgenus CHICOREtJS Moiitlort. 



Chicoreus palma-rosae Mexicana SteaniH. 



= palma-roso^ Liiniaick, var? 

 ? = M. affinis Kefivc. 

 ? = 31. Steerid' Reeve. 



A single example (Mus. No. 40803), in f.iii- coiulition. 



Tlie occurrence on the west coast of any form allied to the palma- 

 rosjB group of Murices has not heretofore been reported. In several 

 instances during my residence in California I noticed worn beach 

 shells of the above in material received from the Gulf of California. 

 The specimens were usually in such pooi- conditi(m as to be of no value 

 as examides for i he cabinet, and the geograi)hical fact of their appear- 

 ance among west-coast shells did not impress me sufficiently, until Mr. 

 Fisher returned from his Gulf expedition with the quite fair speci- 

 men herein listed. It hardly agrees with either of the described 

 forms above lefeired to, neither does it differ greatly. A comparison 

 with the monograplis is not quite satisfactory, aiul the various exam- 

 ples in the National Museum of such forms as it most nearly ap- 

 ])roaches, are not sufliciently numerous to remove the doubt. I have 

 given it the above name, as in other instances in this i)ai)er, solely for 

 the object that the geograi)hical fact may be clinched ami made known. 

 It may ultinuitely i)rove to be a variety of Reeve's affinis, for which he 

 has given no habitat. 



The allies of the form known as palma-rofiw inchuh' the following: 

 M. palmarosw Lamarck, M. Stceria; Reeve, M. SauUd' Sowerby, M. 

 maurus Broderij), and M. affinis Heeve. 



The salient features of the group are well illustrated in the i)rincipal 

 and best known form, the species first named. 



The i'luiracter, number, and arrangement of the fronds upon the var- 

 ices or varical fronds are quite persistent in all of these si)ecies, and 

 they all have minor characteristics in common. 



