238 PROCEEDINGS OF THE ACADEMY OF [1898. 



H. niger (J. G. Cooper). PI. IX, figs. 5, 6j PI. XI, fig. 33; PI. XII, figs. 43-48; 

 PI. XIV, fig. 71. 



Ariolimax niger J. G. Cooper, Proc Acad. Nat. Sci. Phila., 1872, p. 147, 

 pi. 3, f. B, 1-4. W. G. Binney, Terr. Moll. V, p. 234, f. 133 (caudal pore) ; 

 pi. v, f. D, F, (teeth.) ; pi. xii, f. F (genitalia) ; Man. Amer. Land Shells, p. 

 100, f. 64; Terr. Moll, v, Third Supplement, Bull. M. C. Z., XIX, no. 4, p. 

 212, pi. v, f. A, I, C, D (external aspect and caudal pore). Cockerell, Ann. 

 Mag. N. H. (6), vi, p. 278, 279. 



Hesperarion niger Simroth, Malak. Blatter (n. F. ), xi, p. 109-119, pi. 1, f. 

 7-14. 



Ariolimax Andersoni J . G. Coop.?, W. G Binney, Ann. Lye. Nat. Hist. N. 

 Y., xi, p. 182, pi. xii, f. 9 (genitalia), pi. xviii, f. G (teeth) ; Terrestr. Moll. 

 V, p. 235, f. 135, 136, pi. xii, f. E (genitalia), pi. v, f. G (teeth). Man. Amer. 

 Land Shells, p. 132, f. 66, 67. Second Suppl. T. M. V, p. 43. Third Suppl. 

 p. 212, pi. v, f. F. Not Arion Andersoni J. G Cooper. 



Exterior: Upper surface (iu alcoholic specimens) smoky brown- 

 black above, slightly lighter gray-black laterally, unicolored or 

 dappled with black ragged spots ; sole gray-black, with black spots 

 scattered along the inner edge of the lateral areas. Integument 

 obliquely longitudinally grooved, not much reticulated. Mantle 

 with the lung pore submedian ; genital orifice some distance behind 

 the right tentacle, caudal pore conspicuously large and deep, with a 

 cleft extending to the tail ; sole indistinctly tripartite. Length (in 

 alcohol) 30-45 mm. 



The genitalia in two individuals dissected show considerable 

 variation. In one, (PI. XII, fig. 44), the penis is large nearly its 

 entire length, constricted at base; this being from a maculated indi- 

 vidual like PI. IX, figs. 5, 6, from Santa Clara, Cal. In the other, 

 a typical niger in coloring, the penis is slender below, swollen 

 above (PI. XII, fig. 47). We hope to receive further specimens 

 and ascertain the limits and significance of variation iu these 

 organs. 



In one specimen (Mus. no. 71,078) there were thirteen spermato- 

 phores (PI. XII, fig. 43) in the spermatheca. 



Jaw with eleven wide ribs. 



Radula agreeing with Ariolimax in the long, oblique cusps of the 

 marginal teeth. 



Cooper's types were from the neighborhood of San Francisco Bay. 

 Specimens are before us from Bolinas, Haywards, Santa Clara, 

 Stevens' Creek Canyon, Santa Cruz range, 900 feet altitude, and 

 near San Jose. Binney gives the localities Santa Rosa, Healds- 

 burg, Sonoma Co.; and for the synonymous Ariolimax Andersoni, 

 mountains of Alameda Co. The general range, therefore, covers 

 the Coast and Bay counties from Sonoma to Santa Cruz. 



