266 CALLISTOCHITON. 



have no means of knowing whether the C.fimbriatus of Orcutt's San 

 Diego list was identified from Carpenter's earlier type specimen, or 

 his later MSS. Everything considered, the best course open to us- 

 seems to be the selection of an entirely new name. The type is in 

 the collection of the Academy. 



C. INFORTUNATUS Pilsbry, n. sp. PI. 59, figs. 37-42. 



Shell large, regularly ovate, the dorsal ridge obtuse; valves 

 arcuate; muero obtuse, median. Olivaceous, sometimes spotted with 

 paler on the ribs and jugum. 



Central areas having about 12 parallel lirse on each side, decussated, 

 the interstices having square depressions. Lateral areas having two 

 very strong rounded tuberculose ribs. Anterior valve with 9, pos- 

 terior with 7-8 elegantly spreading ribs. 



Interior : posterior valve having 7-8, central 1, anterior 9 slits ; 

 teeth concave outwardly, obtuse, slit at the apices of the ribs, some- 

 times with an intercalated slit or abnormally serrate ; teeth of poste- 

 rior valve very obtuse, hardly sloping ; eaves small, delicate. Sinus 

 wide, flat, but little angular, sometimes crenulated by the riblets of 

 the exterior. Girdle irregularly imbricated with flattened scales, 

 each one about 6-striated (fig. 39.) 



Length 111, breadth 8| mill. 



Equador (Cuming) ; La Paz, W. Mexico (Pease.) 



Callistochiton pulchellus CARPENTER, MSS. Not C. pulchellus 

 Gray, q. v. 



The sculpture of the central and lateral areas resembles that of C. 

 palmulatus, but the tail-valve (figs. 38, 42) is entirely different in form. 

 This shell was sent to Dr. Carpenter by Cuming as the true C. 

 pulchellus of Gray, but it is certainly not that species. The above 

 description and the figures are from Carpenter's MSS. and unpub- 

 lished drawings of his type. 



The shell recorded by Dr. J. G. Cooper from " Catalina (or other?) 

 I., Cal." under the name Callochiton fimbriatus Cpr. MSS., and by 

 Carpenter (in MSS.) from " S. Pedro " (both referring to the same 

 specimen) may be a variety of this species, but no definition of it 

 has been published, the locality is uncertain, and Dr. Carpenter in his 

 later MSS. shifted the name fimbriatus to another species, leaving the 

 form under discussion as a nameless variety of his C. pulchellus. 

 Under these circumstances it has been thought best to expunge the- 

 name fimbriatus from the list of valid species. 



