PANAMIC-PACIFIC PELECYPODA 357 



?Gari (Psammocola) regularis (Carpenter), Hertlein and Strong, 1950, Zoologica, vol. 

 35, pt. 4, p. 218, pi. 2, fig. 10.— Keen, 1958, Sea Shells of Tropical West 

 America, p. 190, fig. 466. 



Shell broadly elongate, nearly equilateral, the anterior end narrowly 

 rounded, the posterior end obliquely truncate. The posterior dorsal area 

 is depressed and marked with fine radially incised lines. Surface speckled 

 and mottled with white and purple spots, the whole covered in life with a 

 golden-brown periostracum. 



Length 46.8 mm., height 25 mm., diameter 15 mm. (Hertlein and 

 Strong). 



This species seems to be limited to the northern part of the Panamic- 

 Pacific province. 



This species was figured by Hertlein and Strong as G. regularis Car- 

 penter but is probably distinct. The type of G. regularis is in the U.S. Na- 

 tional Museum and was recently figured by Palmer, 1958 (Mem. 76, Geol. 

 Soc. America, p. 113, pi. 15, figs. 1-6), and shows a small, thin, plainly 

 marked shell, the posterior area bearing a series of widely spaced, trans- 

 verse lines. G. regidaris should probably be considered a synonym of G. 

 fucata Hinds. 1843, described from Magdalena Bay on the west coast of 

 Lower California. 



Range — Coast of Mexico. 



Garl (Gobraens) panamensls, new species Plate 63, figure 11 



Similar to G. maxima but longer and lower, the beaks placed less 

 centrally and the posterior-dorsal margin is longer and more descending. 

 The posterior side is longer and more attenuated at the end. Texture of the 

 shell thin, internally white with the rays of pattern showing through near 

 the margin. Shell slightly convex, the ground color white rayed with ir- 

 regular bands of a delicate violet-brown. Pallial line indistinct because of 

 the thinness of the shell, the sinus large, complete, and high, reaching to 

 about the middle of the valve. Nymphal plate large and flat. Periostracum 

 light-brown, thin, and varnish-Hke. 



Length 54.5 mm., height 31.6 mm., diameter 16.4 mm. Holotype, ANSP. 



The commonest Gari at Panama, easily recognized by its thin shell and 

 coloration. 



Range — Panama. Panama Canal Zone. Palo Seco. 



Gari (Gobraens) helenae, new species Plate 63, figures 12, 12a 



Shell rather elongate, the length nearly twice its height, moderately 

 convex, the beaks placed nearly central, the valves almost equilateral but 

 are slightly unequal in shape and convexity, the left valve being more con- 

 vex, while the right is depressed across the middle and more strongly flexed 

 along the posterior-ventral margin. The height is greatest on the anterior 

 side of the middle, its end narrowly rounded while the posterior side is 

 narrower and obliquely truncated at its end. The posterior gap between 

 the valves is quite wide. Color under the periostracum is purple with a 

 mottling of rays and patches of dull white, internally the color is purplish 

 with a shading of white. The general texture of the shell is of moderate 

 weight, the external rays showing through indistinctly, the pallial sinus 



