152 TERRESTRIAL AIR-BREATHING MOLLUSKS. 



balance marginals ; a difference of arrangement which may fairly be considered 

 to show a specific difference between his specimens and the San Francisco form, 

 though his discovery leads us to consider Amalia as native to California. 



The oviduct is long and greatly convoluted. The prostate is well developed. 

 The vagina is very short; the very short duct of the genital bladder enters at 

 about its middle. The last-named organ is large, globular. The penis sac is 

 small, short, cylindrical, expanded, and bulbous at its apex, where the vas def- 

 erens enters. I could detect no accessory organs in the single specimen imper- 

 fectly examined (PL XI. Fig. F). 



The genitalia are somewhat of the same type as those of L. flavus, but the 

 dentition of the latter is quite distinct (see above). There is a still stronger 

 resemblance to the genitalia of Amalia yagates as figured by Semper (Phil. 

 Archip., PI. XI. Fig. 9), so far as the penis and genital bladder are concerned. 



Limax montanus, INGERSOLL. 



Color bluish-gray. Form stout, with blunt posterior extremity. Length ex- 

 ceeding one inch. Hot Sulphur Springs, Colorado. 



Limax montanus, INGERSOLL, Bull. U. S. Geol. and Geogr. Survey of the Terri- 

 tories, No. 2. second series, 132 (1875) ; ed. 2 (1876), p. 394, Figs. 

 Limax castancus, INGEKSOLL, 1. c., ed. 2, p. 396. 



The above is Ingersoll's description. Specimens received from him furnish 

 the anatomical details here given. 



It is a species of the Central Province. 



Jaw as usual in the genus. Lingual membrane long and narrow. Teeth 

 50 1 50, with 16 perfect laterals. Centrals with base of attachment slightly 

 longer than wide; inferior lateral angles not much produced, lower margin in- 

 curved ; reflection slightly shorter than one half the base of attachment ; tri- 

 cuspid, the outer cusps short, stout, bearing short, stout cutting points ; the 

 median cusp stout, reaching almost to the lower edge of the base- of attach- 

 ment, beyond which projects the cutting point; laterals like the centrals, but 

 asymmetrical, as usual, by the suppression of the inner cusp with its cutting 

 point and inner lower lateral expansion of the base of attachment. There are 

 16 perfect laterals, beyond which are several teeth forming the usual gradual 

 transition to the marginals. These latter are aculeate, the cutting points bear- 

 ing at about the centre of their lower edge a blunt spur, which is a modified 

 form of the bifurcation of the marginal teeth often found in Limax. The mar- 

 ginal teeth have the usual characteristic arrangement in oblique rows, and the 

 separate teeth, as they pass outward, have at first the rapid increase for a short 

 distance, and thence gradual decrease in size, usual in Zonites. 



In the genital system (PL XII. Fig. B) there are no accessory organs. The 

 penis sac is as long as the vagina, with a constriction near its commencement, 

 and tapers above to a point, below which it receives the vas deferens. The 



