NO. 12 STRONG AND HERTLEIN : MARINE MOLLUSKS 227 



Fossarus sp. 



Three specimens belonging to this genus were dredged off Taboga 

 Island, Panama. This genus is credited with 13 species from the west 

 coast, all briefly described and none figured. 



Iselica kochi Strong & Hertlein, new species 

 Plate 19, Fig. 11 



Shell small, ovate, grajn'sh white; nucleus minute, depressed, smooth, 

 polished, of a little more than 1 whorl; postnuclear whorls 2^, rapidly 

 enlarging, well rounded, sutures impressed; spiral sculpture of strong, 

 equal and equally spaced cords, of which 4 appear between the sutures 

 and 8 on the body whorl; axial sculpture of finer, closer spaced, re- 

 tractive riblets in the interspaces between the spiral cords, which ride 

 up on the sides of the cords but do not cross the summits; umbilicus 

 moderately large, deep, bounded by the lower spiral cord ; aperture oval, 

 outer lip scalloped by the ends of the spiral cords; columella slender, 

 curved, with a distinct swelling in the middle; body with a thin callus. 

 The type measures: length, 1.5 mm; diameter, 1.2 mm. 



Holotype: No. 727 (Calif. Acad. Sci. Paleo. Type Coll.), from 

 Loc. 27,229 (C.A.S.), dredged in from 3 to 9 fms. in Bahia Honda, 

 Panama. L. G. Hertlein collector. Three additional specimens were 

 dredged at the same locality. 



While these specimens are probably not fully adult, the species 

 would seem to be even smaller than Iselica maculosa Carpenter, ^^ de- 

 scribed from Mazatlan, Mexico, and much smaller than the other more 

 northern species. They lack the shouldered whorls and colored spots by 

 which Carpenter distinguishes Iselica maculosa from the larger Iselica 

 ovoidea Gould. ^- None of the 4 specimens retains any epidermis. 



This species is named for Mr. Karl Koch, ornithologist of the San 

 Diego Zoological Society, who accompanied the expedition. 



5i/ja/)ij maculosa Carpenter, Mazatlan Catalogue, [1855-] 1857, p. 355. 

 "Mazatlan." 



^'Narica ovoidea Gould, Boston Jour. Nat. Hist., vol. 6, October, 1853, p. 

 380, pi. 14, fig. 10. "Purchased at Mazatlan." [According to Dall (U. S. Geol. 

 Survey, Prof. Paper 59, 1909, p. 204) this paper was issued in advance of the 

 Journal, separately, April, 1852.] 



