196 INVERTEBRATA OF MASSACHUSETTS. 



over rich or cultivated ground, whether lowland or upland, and 

 may be found in dry weather partially sheltered by sods, or lying 

 along by the side of stones, where it may enjoy the benefit of the 

 moisture condensed by these bodies. 



The animal is very similar to that of S. ovalis, but in general 

 the markings are darker, and the marbled appearance which its 

 viscera exhibit through the transparent shell, combines yellow 

 instead of whitish colors. Radiating lines of furrows also are 

 quite conspicuous on the posterior part of the foot. 



It is extremely probable that this, is after all, the S. amphibia of 

 Europe. No distinct and constant difference can be pointed out be- 

 tween them. In specimens of the foreign shell which I have seen, 

 the surface may perhaps be a little more glossy, and the shell may 

 have somewhat more of an appearance of solidity. Like that shell, 

 too, it varies considerably in the prominence of its spire. 



I think there can be no doubt that our shell is the true S. campestris 

 of Say, though it presents nothing which would suggest the character 

 of " white and vitreous lines, irregularly alternating." 



SUCCI'NEA AVA'RA. 



Shell very thin, wrinkled, yellowish, whorls three, rounded ; 

 suture deep ; aperture rounded, ovate, more than half as long as the 



shell. 



FIGURE 127. 



State Coll., 85. Soc. Cab., No. 1256. 



Succinea avara ? SAY ; Long's 2d Expedition, Append., 200, pi. 15, f. 5. 

 Succinea vermeta, SAY ; New Harmony Disseminator. 



Shell rather small ; very thin and fragile, of a deep straw- 

 color ; surface irregularly wrinkled ; whorls about three and a 

 half, well rounded, and separated by a deep suture, the last whorl 

 composing the greater part of the shell, but not very broad ; 

 aperture in adult and elongated shells, about half as long as the 

 shell, but generally proportionally shorter, of a rounded form, the 

 curve of the outer lip, where it joins the preceding whorl, being 

 so great as to render the aperture nearly as broadly rounded be- 

 hind as in front. Length /^ inch, breadth 5 T inch, divergence 

 56. 



