CLASS GASTROPODA 
21 
Type in United States National Museum. Type locality, Monterey, 
California. 
Range. Trinidad to San Pedro, California. 
Tritonalia circumtexta citrica Dali, 1919 
Proceedings of the United States National Museum, 56:334. 
This is a variety which, when fresh, presents a ground color of lemon 
or orange-yellow instead of the usual grayish-white, while the brown 
bands are much less emphatic and the shells are usually smaller than 
those of the type. (Dali.) 
Type in United States National Museum, No. 56747. Type locality, 
Catalina Island, California. 
Range. Santa Barbara Islands to Scammons Lagoon, Lower Cali¬ 
fornia. 
Tritonalia interfossa Carpenter, 1864 
Plate 30, fig. 2 
Proceedings, Philadelphia Academy of Natural Sciences, 64. Tryon, Manual of 
Conchology, 2; PI. 39, fig. 484. 
Shell narrower and more shouldered than T. hirida, the lattice of 
revolving larae and longitudinal ribs coarser and more elevated; canal 
short, closed. Length, .4 to .75 in. (Tryon, Manual of Conchology.) 
Range. Sitka, Alaska, to California. 
Tritonalia interfossa clathrata (Stearns) Dali, 1919 
Proceedings of the United States National Museum, 56:334. 
This is a short and stout form with very prominent rectangular clath- 
ration and flatly turreted spire, which was distinguished by Dr. R. E. 
Stearns in manuscript many years ago but never published. (Dali.) 
Type in United States National Museum, No. 177995. Type locality, 
Avalon, Catalina Island. 
Range. Monterey to Catalina Island, California. 
Tritonalia interfossa minor Dali, 1919 
Proceedings of the United States National Museum, 56 :334. 
This is a pale, dwarf, slender form, also from Catalina Island, which 
seems nevertheless to have reached maturity. It is strongly clathrate. 
Height, 7; diameter, 3.5 mm. (Dali.) 
Type in United States National Museum, No. 56912. Type locality, 
Catalina Island, California. 
Range. Known only from type locality. 
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