ARION. 451 



Arion fuscus. 



Color whitish or hght ashy, sometimes with a tinge of brown, or dark grayish; 

 body cylindrical, narrow, ex[)anding a little towards its extremity, ending in a 

 flat and rounded termination ; head darker than the body, projecting very little 

 beyond the mantle ; mantle small, oval, narrow ; disk of the foot whitish. A 

 triangular mucus-pore on the upper surface of the posterior extremity. 



Li max fuscus, IMuller, Hist. Vcim. ii. 11 (1774). 



Arion hoiteiisis, Feuussac, Hist. 65, pi. 2, tiys. 4, G; Suppl. pi. 96 a (1819). — Binney, 

 Bost. Jouru. N. II. iv. 170 (1842) ; Terr. Moll. ii. 27, pi. 64, tig. 1 ; pi. 65, fig. 2 

 (18.-,!). — Leidv, Terr. Moll. U. S. 249, pi. 2, figs. 1-4, aiiat. (1851).— De Kav, 

 N. Y. Moll. 2;3 (1843).— IliiEVE, Brit. L. and Fr. W. Moll. 11, tigs. 



Arion fuscus, Moquin-Tandon (which see fur furtJier foreign synonymcs). 



Color wliitish or light ashy, sometimes with a tinge of brown, or 

 dark grayish ; an obscure, iil-dcfined, dark colored line or band 

 rises where the mantle 



Fig. 711. 



meets the bases of the 

 tentacles on both sides, 

 and, extending along 

 the whole length of the 

 mantle to its posterior 



A. fuscus. 



extremity, converges 



towards the line of the opposite side ; another band, proceeding from 

 under the posterior edge of the mantle, not quite continuous with 

 the above described line, runs along the sides of the body to its ex- 

 tremity. Body cylindrical, narrow, when extended very much elon- 

 gated ; expanding a little towards its extremity, and ending in a 

 flat and rounded termination ; its upper surface is covered Avith nar- 

 row, oblong, prominent glands, appearing sometimes as if carinated, 

 and arranged in parallel rows, the flanks with elongated tubercu- 

 latcd ])lates and finer granulations. Head darker than the body, 

 projecting very little beyond the mantle. Eye-peduncles blackish, 

 one eighth the length of the body, stout, bullis translucent, ocular 

 spot at the superior part, black. Tentacles immediately under the 

 eye-peduncles, very short, conical. Mantle small, oval, narrow, 

 commencing just behind the insertion of the eye-peduncles, less 

 than one third of the length of the animal ; covered with granula- 

 tions tending to a vermiform shape. Disk of the foot whitish, witii- 

 out a separate locomotive band, the marginal boundary between it 

 and the l)ody marked by a furrow, projecting beyond the body pos- 

 teriorly. Respiratory foramen small, with a cleft to the margin of 

 the mantle. Between the eye-peduncles is a tubercular ridge with 



