420 LEPIDOPTERA. 



coons are very small, almost round, tough, and parchment- 

 like, and are fastened to the twigs of the plants on which 

 the insects live. The moths of some, if not of all, of the 

 Limacodes make their escape by pushing off one end of the 

 cocoon, which separates like a little circular lid. 



The most common of these slug-caterpillars, in Massa 

 chusetts, live on walnut-trees. They come to their full 

 size in September and October, and then measure five eighths 

 of an inch in length, and rather more than three eighths 

 across the middle. The body is thick, and its outline nearly 

 diamond-shaped ; the back is a little hollowed, and the mid- 

 dle of each side rises to an obtuse angle ; it is of a green 

 color, with the elevated edges brown. The boat-like form 

 of this caterpillar induced me to name it Limacodes Scapha, 

 the skiff Limacodes, in my " Catalogue of the Insects of 

 Massachusetts." My specimens generally died after they 

 had made their cocoons, and consequently the moth is un- 

 known to me. 



The moth of a Limacodes, called Cippus * (Fig. 207) by 

 Sir J. E. Smith, is sometimes found 



Kg. 207. 



in Massachusetts, from the middle of 

 July till the 10th of August. It is 

 of a reddish-brown color ; on each of 

 the fore wings there is a small dark 

 brown dot near the middle, and a broad 

 wavy green band beginning at the base, and bending round 

 till it touches the front margin near the tip ; behind a deep 

 notch of this band, near the base of the wing, there is a 

 triangular tawny spot, and another smaller one near the 

 tip. The green band is sometimes broken into three tri- 

 angular green spots, the middle one of which is wanting 

 in some specimens. One half of the stalk of the antennae 

 of the male is doubly feathered beneath ; the remainder to 



* Probably not the true Cippus of Fabricius, which is found in Surinam. 

 There is a figure of our species in GueVin's " Iconographie du Regne Animal," 

 where it is named Limacodes Delphinii, but for what reason I know not, for it 

 doe* not live on the Delphinium or larkspur. 



