888 Report oF THE State GEOLOGIST. 
branches near the transverse band with the descending branches 
just in front of the oral processes. 
Fias. 595,596. Laqueus Californicus, Koch (sp.). (DAvipson.) 
Type, Laqgueus Californicus Koch (sp.). 
Distribution. Recent (Boreal, Japanese and Californian Proy- 
inces). 
Trigonosemus, Koenig. 1825. 
Synonyms; Sissurirostra, dOrbigny, 1847;  Fissirostra, 
d’Orbigny, 1848; Delthyridea, King, 1850. 
Shells planoconvex ; surface radially plicate. Pedicle-valve 
with arched and prominent beak, sharply defined cardinal area, 
Fias. 597-600. Trigonosemus elegans, Koenig. (Davipson.) 
and minute apical foramen bounded beneath by coalesced deltidial 
plates. Cardinal process highly developed, bilobed. Loop as in 
TeREBRATELLA, but more narrow and elongate. 
Type, Zrigonosemus elegans, Koenig. 
istribution. Cretaceous. 
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