206 UMAX. 



faculty as L. arborum, of letting itself down from one branch 

 of a tree to another or to the ground, by means of a slimy 

 thread. Mr. Norman informs me that in the earlier part of the 

 year this slug is usualty creamy white or light-drab , that as the 

 summer passes away it assumes a darker hue, and brown flakes 

 are more or less thickly scattered over the surface ; and that 

 during the autumn it is frequently of a rich brown color." 

 Brit. Conch., i, 134. 



Introduced from Europe, it has become a common species in 

 the States of our Atlantic seaboard ; a considerable number 

 often congregating in the same retreat, whence they sally in the 

 night to feed. Binney observes that: "Their growth is rapid, 

 the animal excluded from the egg in the spring arriving at 

 maturity, and producing eggs before the succeeding winter. 

 They defend themselves from injurious contact by instantly 

 secreting, at the part touched, a quantity of milky white, 

 glutinous mucus. They are active in their motions, and soon 

 escape when disturbed. Suspending themselves head down- 

 wards, they lower themselves from plants and fences by forming 

 a mucous thread by which they attach to the point from which 

 they hang. They are occasionally seen in this situation in rainy 

 weather. During the process of excreting the mucous thread, 

 the alternate undulating expansions and contractions of the loco- 

 motive band of the foot are seen to take place, in the same manner 

 as when they are in motion on a plane surface." L. and F W. 

 Shells, pi. 1, 64. 



The synonymy includes* L. obliquus, Brard ; L. tunicatus, 

 Gould ; L. Mentonicus, Nevill ; L. Niciensis, Bourg. 



The remarks upon the change of color in these slugs, quoted 

 above from Jeffreys, show how little value is to be attached to 

 color varieties. The following are given by Lessona and Pol- 

 lonera : 



Var. TYPUS (var. albidus, Pini). Ash-colored, head and tentacles 

 brownish (fig. 92). 



Var. FILANS, Hoy (fig. 91). Whitish, shield yellowish. 



Yar. AUBATUS, Lessona. Animal unicolored, yellowish, tentacles 

 black. 



