CLASS PELECYPODA 
181 
its smaller lunule, shorter and weaker right lateral tooth, and sharper and 
more delicate concentric sculpture. It is a rare form and doubtless the 
two descended from the same Oligocene ancestors. (Dali.) 
Type in U. S. N. M. No. 211729. Type locality not given. 
Range. Catalina Island, California, to Acapulco, Mexico. 
Semele incongrua Carpenter, 1863. 
Plate 11, figs. 12, 13. 
Suppl. Rep. Brit. Assoc., p. 640. Proc. Cal. Acad. Sci., 3:208. 
S. t. forma et indole S. "pulchra” simili, sed sculptura diversa; trans- 
versa, tenuii, subplanata, umbonibus prominentibus; pallide carnea, radiis 
intensioribus ornata; tota superficie minute et creberrime raditim striulata; 
marginibus dorsalibus postico rectiore, antico parum incurvato; reliquis 
regulariter excurvatis, parte antica diagonaliter valde producta; v. sinistr. 
liris crebris subacutis concentricis, antice saepe irregulariter interruptis, 
postice circiter quaternis solum conspicuis extantibus; v. dextr. liris 
paucioribus, acutis, antice vix interruptis, postice alternantibus, extantibus; 
intus; dent. card, parvis, fossa cartilaginali angusta elongata; dent. lat. v. 
dextra, elongatis, regione cardinali purpureo tinctis; cicatr. adduct, subro- 
tundatis; sinus pallii maximo, ovali, ascendente, per quintas inter sex 
totius interstitii partes porrecto; colore secundum paginam externam tincta 
et radiata. Long., 0.58; lat., 0.40; alt., 0.16. (Carpenter.) 
Like S. pule hr a , with concentric sculpture differing in right and left 
valves, fine radiating striae all over. (Carpenter.) 
Type in California State Collection, No. 1061. Type locality, Santa 
Barbara, California. 
Range. Monterey, California, to the Coronado Islands, Lower Cali¬ 
fornia. 
Semele pulchra Sowerby, 1832. 
Proc. Zool. Soc., 1832, p. 57. Conch. III., Amphidesma; fig- 2. 
Amph. testa ovali, pallida, superficie concentrice striata; intus albida, 
purpureo-varia; latere postico breviore; margine antica inclinata, striis 
nonullis radiantibus, strias incrementi decussantibus. Long. 1 %o 5 lat. 
4 / 10 ; alt., 1 poll. (Sowerby.) 
Shell oval, pale, surface concentrically striated; whitish within, varie¬ 
gated with purple; posterior side shorter, anterior margin inclined, rayed 
with a few striae crossing the striae of growth. (Conch. Iconica.) 
This species was described as Amphidesma pulchrum. 
Type in Cuming Museum. Type locality, Bay of Caracas, S. America. 
Range. Monterey, California, to Ecuador. In the Pleistocene at San 
Pedro and San Diego, California. 
