NO. 1312. SYNOPSIS OF THE VENERIDJi—DALL. 393 



confusion. It can he discriminated from C. undateJla l)y its coarser 

 and more distant sculpture and the fact that in the adult the ribs of 

 the middle of the lower half of the disk generally are thickened and 

 flattened, showing a polished surface which nearly covers the inter- 

 spaces. Y. californiana Conrad, 1S37; Y. californlensk Broderip. 

 1835; T" lemodon Sowerb}^, 1835; Y. simillima Carpenter, 1857. not 

 of Sowerby, 1853; and Y crassa (Sloat, MS. in) Carpenter, 1864, are 

 .synonymous. 



CHIONE (CHIONE) COMPTA Broderip, 1835. 



Peru and northward to the Gulf of California in 21 to 20 fathoms. 



This species has the concentric ribs few and veiy distant, is rela- 

 tively flatter than C. siwcincta of the same size, and the pallial line 

 is hardly sinuated and is unusual^ distant from the ventral margin of 

 the valves. Ycnus calif oriiica Carpenter, 1850 and 1872, is this 

 species, the name arising from an error of the types. 



CHIONE (CHIONE) SUBROSTRATA Lamarck, 1818. 



Mazatlan, Central American coast, and south to Payta. Peru. Also 

 on the Atlantic coast. 



This is Yenus. crenifera Sowerby, 1835; T" porteslana Orbigny, 

 1816; Y. heau! Recluz, 1852; and probably Y. lunularl>< Philippi. 

 1811. Carpenter, in 1863, identified Y. sngiUata Reeve with this 

 species. 



CHIONE (CHIONE) PURPURISSATA Dall, 1902. 



Cape St. Lucas and the Gulf of California. 



This beautiful species, with the interior of the disk rosepurple, was 

 figured b}" Reeve ^' as a variet}^ of Yenus crenulata of the West Indies 

 (b}^ which Chione pabera Valenciennes is meant), and was named 

 variety lilacina by Carpenter, 1861; but it is not Chione lilacina 

 Gray, 1838, and so a new name is proposed for it. It is a rounder shell 

 than C. puhcra^ with less prominent lamellation, especially on the pos- 

 terior slope, which, in this species, is often wholly destitute of lamelhv. 



CHIONE (CHIONE) PULICARIA Broderip, 1835. 



Gulf of California from its head to Guaymas and south to Chiriqui, 



West Colombia. 



This is Yena^ chujnJxfa Reeve. 1863, not of Lamarck, 1818; and Y. 

 ■p!)iaixite)i!^!x (Sloat, MS. in) Carpenter, 1861. This species is the Pacific 

 analogue of O. mtapiirpurea Conrad^ of the Atlantic fauna, but a more 

 elongated and pointed species. 



It is Yenus pfcfferl Dunker, MS., according to Romer, 1867. 



« Conch. Iconica, Venus, pi. xiii, fig. 46, 1863. 



