238 A MANUAL OF AMERICAN LAND SHELLS. 



and it is ouly by close comparison that their differences can be seen. 

 The present species, although considerably smaller, is nearly allied to 

 Limax agrestis. Its differential characters are as follows: It is always 

 much smaller, and at all ages possesses a peculiarly gelatinous or semi- 

 transparent consistency. The tuberosities of the surface are more 

 prominent in proportion to their size, are not flattened or plate-like, 

 and are not separated by darker- colored anastomosing lines, the inter- 

 vening furrows being of the same color as the general surface. It does I 

 not secrete a milky mucus at evei y part of the surface when touched. 

 Like that species, it is active in its motions, and suspends itself by a 

 thread of mucus. In its genitalia (Terr. Moll., I, Plate II, Fig. 5-6) it 

 differs widely in wanting the curious trifurcate gland to the penis sac 

 found in agrestis^ and in the shape of the genital bladder and length of 

 its duct. 



This species appears to be common to all the northern parts of the 

 United States. It is found under decaying wood in the forests an^ 

 in open pastures, and under stones at roadsides. From its wide dis- 

 tribution it would seem to be indigenous. 



Its testaceous rudiment is minute and delicate in porportion to the 

 small size of the animal. 



Mr. Gwyn Jeffreys (Ann. Mag. Nat. Hist., 1872, 245) suggests the ; 

 identity of campestris with ki'vis, Miill., a European species. Lehmann's 

 figures of the genitalia and dentition of that species show that there is 

 no foundation for any such opinion. 



Jaw as usual in the genus. Ends pointed, recurved; center with a ^ 

 transverse, strong line of reinforcement; median projection sharp. 



Lingual membrane (Terr. Moll., V, Plate, I, Fig. I) : One specimen 

 has 40-1-40 teeth, with 18 perfect laterals on each side. Another . 

 gives 3C- 1-36, with 11 perfect laterals. The centrals and laterals are 

 of the same type as described below in L. agrestis, excepting that there 

 is no peculiar inner side cutting point to the first laterals. About 

 half of the marginals are bifid. I find great difficulty, however, in de- 

 tecting any bifurcation on the extreme marginals. As stated above, 

 Heynemann's figure of the dentition of L. Wcinlandi could not have 

 been drawn from this species. I have no information in regard to L. 

 Weinlandi other than what I find in Malak. Blatt.,X., 212, Plate III, Fig. 

 1. Judging from the dentition alone, I should hardly consider it distinct 

 from agrestis, excepting in its wanting the peculiar inner side cutting 

 point to its first laterals. 



