North American Helices. 27 



W. G. Binney and myself are enabled, from personal obser- 

 vation, to corroborate the statement of Dr. Binney as to the 

 existence of the mucous pore in fuliginosa and laevigata, and 

 have noticed it also in kopnodes. Looking at the forms of the 

 shells, I assume its presence in friabilis and caduca, and suspect 

 that it will be found in siibplana and sculptilis, although the 

 latter has considerable affinity with indentata. 



Gray (Catal. of Pulmonata, 1855) has the genus Zonites in 

 the Family Arionidse, but in a paper, " On the Arrangement of 

 the Land Pulmoniferous Mollusca into Families''' {Ami. and 

 Mag. of Nat. Hist. VI, 3d Series, 267, 1860), he suggests im- 

 portant changes in the arrangement proposed in the Catalogue. 



In the paper referred to he thus characterizes and remarks 

 on the family Parmacellidse, to which, as I understand it, he 

 anticipates that Zonites will be found to belong : 



" Mantle central, large, shield-like, free in front, more or less covered 

 with a spiral shell. Young and adult alike. Foot truncated behind, 

 with a subterminal gland. Parmacellus, Marietta, Laconia (Cat. pp. 

 62, 63), Vitrinella, JVanina, and the allied genera, will probably be 

 found to belong to this family when the animals are more closely exa- 

 mined." 



With the description of Zonites, in which he places one Ame- 

 rican species only (euryomj)halus Pfr., from Guatemala), Gray 

 introduces an account from Ferussac (Tab. Sys. 10) of the 

 animal of II. algira I., the type of the genus, in which the fol- 

 lowing occurs : — " If the mucous pore does not exist in this 

 species as in the Arions, a well marked slit is to be observed in 

 its place, to which the grooves on the upper part of the foot 

 tend." 



Albers thus describes the Genus Zonites : — 



"Zonites Montfort. T. umbilicata, orbiculato-convexa vel depressa, 

 striata vel decussata, subtus laevis, nitida; anfr. 6-7 sensim accrescentes ; 

 apertura obliqua, lunaris ; perist. rectum, acutum, intus leviter labiatum. 



" Maxilla magna, simplex, parum arcuata, a latere attenuata, medio 

 tuberculo valido, rostrilbrmi munita. Palpi labiales distinct!. Poms 

 mucosus oblongus in apice pedis. Radula denticulis marginalibus elon- 



