92 
MARINE SHELLS OF WEST COAST OF NORTH AMERICA 
Lyonsia arenosa Moller, 1842. 
Index Moll. Gronl., p. 20. Zool. Beechey’s Voy.; pi. 43, fig. 3. 
Testa transversini ovata, inaequilatera, ventricosiori, opaca, alba, antice 
obtusa, postice dilatata, superne subangulata, vix hiante; epidermide 
cinerea, arena agglutinata. Diameter, 6.5. (Moller.) 
This yellowish, short and solid species is well distinguished from any 
of the others. Cat. No. in U. S. N. M. 223476. (Dali.) 
Type locality, Atlantic. 
Range. Arctic Sea to the Aleutian and Kodiak Islands, Alaska. Also 
Japan and Circumboreal. 
Lyonsia gouldii Dali, 1915. 
Mex. and Cal. Shells , p. 17; pi. 15, fig. 6 (new name for L. nitida Gould, 1851). 
T. transversa, subfalcata, ventricosa, tenuis, lucida vivde margaritacea, 
concentrice undulata, plerumque nuda; apice ad trientem anteriorem; 
extremitate antica rotundata; extrem. postica attenuata, truncata, sub- 
adscendente, utraque extremitate lineis radiatibus remotis striata. Long., 
%; lat. et alt., % poll. (Gould.) 
More inequilateral, more recurved, more pearly and free from striae 
than O. hyalinum. The species was described as Osteodesma nitidum 
Gould. 
Type locality, Santa Barbara, California. 
Range. San Francisco Bay to Point Abreojos, Lower California. 
Lyonsia striata Montagu, 1815. 
Trans. Linn. Soc., 2:188; pi. 13, figs. 1, a. 
Shell small, slender, with the posterior dorsal margin nearly straight 
and more sharply truncate, while in L. norvegica it is concavely arcuate; 
the test is almost translucent, the form less inflated, the dorsal and, in many 
cases, the basal edges near the margin, conspicuously compressed, the 
umbos nearer the anterior end; and the surface with usually a much 
greater profusion of adherent sand grains than in L. norvegica. (Mon¬ 
tagu.) Cat. No. in U. S. N. M., 213722. 
Type locality, Atlantic. 
Range. Aleutian Islands to Juan de Fuca Strait. Circumboreal. 
Subgenus Allogramma Dali, 1903. 
Lyonsia amabilis Dali, 1913. 
Proc. U. S. N. M., 45 :594. 
Shell thin, with a pale, olivaceous periostracum and pearly interior, the 
lithodesma small. The sculpture resembles closely that of the type group, 
