THE NAUTILUS. 41 
Subgenus Symmorphomactra Dall, 1894. 
Teeth of Mactrotoma, ss.; hinge of Spisula. 
Spisula (Symmorphomactra) falcata Gld., 1850. Comox, Br, Col. to San Pedro, 
Cala. 
Genus MULINIA Gray, 1857. 
Mulinia pallida Brod. & Sby., 1829. Panama to C, St. Lucas. 
+ M. donaciformis Gray, 1839, not of Reeve, 1854; + M. angulata 
(Gray) Reeve, 1854; + M. carinulata (Desh.) Reeve, 1854, (young 
shells) ; ?=M. goniata Desh., 1854, (unfigured and insufficiently 
described) ; +. bistrigata Moérch, 1862. 
Mulinia modesta Dall, 1894. Guaymas, Mexico. 
-+-M. carinulata Cpr. non Deshayes. 
Mulinia Gabbi Tryon, 1869. Lower California. 
Mulinia coloradoensis Dall, 1894. Gulf of California, at Guaymas and thence to 
the Colorado-mouth. 
Mulinia coloradoensis var. acuta Dall, 1894. Colorado river-mouth, Gulf of Cali- 
fornia, 
Mulinia Bradleyi Dall, 1894. Panama, Bradley. 
GenusGNATHODON Gray, 1831. 
Subgenus RANGIANELLA Conrad, 1863. 
Gnathodon (Rangianella) mendicus Gould, 1851, Estuaries, Gulf of Cal, 
+ G. trigonus Petit, 1853; -+-G. truncatum Petit, 1853. 
Subfamily PrERopsin»®. 
Genus LABIOSA (Schmidt) Moller, 1832. 
Labiosa anatina Spengler, 1802. West Mexico. 
+L. pellucida Schum., 1817; +M. cyprinus Gray, 1828; +L. 
papyracea (Lam.) Sby., 1824. 
Subgenus Raeta Gray, 1858. 
Labiosa (Raeta) undulata Gould, 185!. San Pedro, Cala., to Panama. 
+R. californica Melvill, as of Sowerby. 
