PACIFIC COAST SPECIES. 105 



quadrate marginal teeth of the lingual membrane, and by the anterior 

 positioi} of its respiratory orifice. The genus is allied to Arion by its 

 ribbed jaw, its quadrate marginal teeth of the lingual membrane, and 

 by the anterior position of its respiratory orifice ; it differs in having 

 an internal shell, in the position of its generative orifice, and by the 

 want of a caudal mucus pore. The genus is also allied to ArioUmax 

 in having a ribbed jaw, quadrate marginal teeth to its lingual mem- 

 brane, and an internal shell ; it differs in the position of both genital 

 and respiratory orifices, and by the want of a caudal mucus pore. The 

 absence of a distinct locomotive disk to the foot distinguishes our genus 

 also from Arion, Limax, and ArioUmax. It is not readily confounded 

 with any other known American genus. The Irish genus Geomalacus 

 is somewhat allied, having an anterior respiratory orifice and an in- 

 ternal shell, and quadrate marginal teeth. Geomalacus, however, dif- 

 fers frgm Frophysao'n in having an extremely anterior mantle and ori- 

 fice of respiration close behind the right tentacle. It also has a loco- 

 motive disk and caudal mucus pore. The genus is treated as a sub- 

 genus of Anadenns by Dr. Fischer in his '' Manuel," but the position 

 of the orifice of respiration is posterior in that genus. 



Propliysaon Heniphilli. 



Body blunt anteriorly, attenuated posteriorly, rounded and high on 

 the back. Mantle granulated, whitish with a circular ring of smoke- 

 color above the respiratory orifice. Body obliquely reticulated with 

 bluish lines, the reticulations larger (about twelve) below each side of 

 the mantle, more numerous and smaller on the posterior extremity of 

 the body. These reticulations are subdivided by irregularly disposed, 

 rounded tuberosities, with colorless interstices. Above the foot, from 

 the longitudinal line running around the animal to the edge of the foot 

 are perpendicular lines or furrows, also bluish in color. The foot has 

 crowded wrinkles, running obliquely backwards from its oeuter to its 

 margins. Length of an alcoholic specimen, 40™"". (See Fig. 68.) 



Prophysaon HempMlli, Bland and W. G. Binney, Ann. Lye. Nat. Hist, of N. Y., X. 

 293, PI. xiii. fig. 8 (1873).— W. G. Binney, Terr. Moll., V. 



Forest Grove and Astoria, Oregon ; the variety at Oakland and Men- 

 docino County, California ; thus it is found in the Pacific Province, in 

 the vicinity of the sea. 



The internal shell (Fig. 70) differs in thickness, but is always well 



