166 Binney on the Naked Air- Breathing Mollusca 



as Limax agrestis. I have never seen it suspend itself by a 

 mucous thread. 



This species is of foreign origin, but the period of its intro- 

 duction is not known. It may probably exist in other cities 

 as well as in Philadelphia, or even in the country not far dis- 

 tant from the sea-coast. It was noticed by Mr. Say, more 

 than twenty years since. 



LIMAX AGRESTIS. 



L. corpore albo, griseo, cinereo, rufescenle aut nigrescente, unicolore aut 

 maculato, sub-c^lindraceo, glandulis elongatis et sulcis fuscis reticulatis in- 

 structo ; cljpeo anteriore, ovali, gibboso, lineis concentricis striate; carina 

 brevi ; aperturd laterali postica. 



SYNONYMES AND REFERENCES. 



Limax agrestis, linnjEUS. Syst. Nat. I2th edit. p. 1082. 

 MULLER. 2d part. No. 204, p. 8. 

 DRAPARNAUD. Hist. des. Moll.p. 126, ^Z. 9,^0^.9. 

 FERUSSAC. Tableau Syst. p. 2\. 



Hist, des Moll p. 73, pi. 6, Jig. 7—10. 

 Supplement, p. 96. 

 LAMARCK. Anim. sans Vert. 2d. edit. l.p. 717. 

 Limax tunicata, gould. Invertehrata of Mass. p. 3. 



DESCRIPTION. 



Color varying from whitish through every shade of cin- 

 ereous and gray to black, and through various shades of yel- 

 lowish, or amber-color, to brownish, and sometimes irregularly 

 spotted with small black points or dots ; tentacles darker than 

 the general surface, sometimes black ; mantle sometimes 

 mottled with a lighter color ; base of foot sallow white ; 

 sheath of tentacles indicated by black lines extending back- 

 wards from their base under the edge of the mantle. Body 

 when in motion cylindrical, elongated, terminating acutely, 

 the sides towards its posterior extremity compressed upwards, 

 so as to form a short carina or keel ; foot very narrow. Man- 

 tle oblong-oval, fleshy, convex and prominent, rounded at 

 both extremities, equalling in length one-third of the length 

 of the body, its surface marked by prominent, irregularly 

 waved, concentrical lines and furrows, having their centre or 



