398 PROCEEDINGS^ OF THE NATIONAL MUSEUM. 



referred to this species should be united with F. thaea Molina, which 

 occurs there abundantly. It is one of the common market clams of 

 California, and is even canned for export. 



There are a number of recognizable varieties which will be noted. 

 The typical form is elegantly radially ribbed with fine even riblets, 

 the concentric sculpture inconspicuous, the color yellowish white with 

 pale purplish l)rown maculations. This variety has been collected at 

 Crescent City, California, and occurs from thence southward to the 

 limits of the range, though the species is not abundant an^^where south 

 of Monterey, California. 



Conrad's original specimens came from Santa Barbara and 8an 

 Diego. Absolute synonj^ms of the t3^pical form are Yenus mundidus 

 Reeve, 1863; Chione straminea Deshayes, 1853, but not of Sowerby, 

 1852; and Veiius disjMr and amplkita (Gould MS.) in Carpenter, 1857. 



PAPHIA STAMINEA var. PETITI Deshayes, 1839. 



This is the most common form of the species, the form especially 

 abundant north of the Columbia River. It is larger than the southern 

 variety, of a yellowish, chalky white, or dull gray color, without 

 maculations; and the separation of the sculpture into areas is often 

 well marked. 



It was described as Venerujjis and afterward referred to Saxidonnis 

 by Deshayes. It is Venus rigida Gould, 1850 (not of Dillwyn, 1817), 

 in major part, and Tcqyes diversa Sowerby, 1852. 



PAPHIA STAMINEA var. LACINIATA Carpenter, 1864. 



Monterey, California, to San Diego. 



This extremely elegant variety is evenly reticulated b}" concentric 

 and radial sculpture, and derives its individuality from the develop- 

 ment of small prickles or spines at each intersection. When these 

 spines are worn off it can not be separated from the variety pet it i^ but 

 with them it is unmistakable. 



PAPHIA STAMINEA var. RUDERATA Deshayes, 1853. 



This form, which is found chiefly in the north, is characterized by 

 the turgidity and prominence of the concentric sculpture, which 

 becomes more conspicuous than the radial ribs. Occasionally the 

 shells are delicate and elegant, but usually specimens of this variety 

 are rude and irregular, coarse and unattractive. It was referred to 

 Chione b}^ Deshayes, and sometimes it looks not unlike Marcia hen- 

 nerleyi^ which, however, has no radial sculpture. 



PAPHIA STAMINEA var. ORBELLA Carpenter, 1864. 



This variet}' comprises those specimens which have nestled in the 

 borings of the large Pholads of the coast, especially at Monterey, and 

 have been obliged to grow into an abnormally swollen and tumid 



