THE NAUTILUS. 85 
sembles the periostracum of the shell of a Limax maximus which 
remains when the shell has been decalcified in weak acid. 
In some of the shells extracted from specimens from Hudson, 
Ohio, a portion of the delicate membrane contains a few gran- 
ules of what appear to be calcareous crystals. In outline the 
rudimentary shell is irregular, the membrane becoming very 
thin, delicate and transparent at the edge. In some specimens 
it was folded on itself, but the general tendency is for it to be 
oblong rather than oval, and in outline, not unlike the shell of 
Timaz maximus. Specimens trom the following localities were 
examined, in all but one of which the rudimentary shell was 
found. 
& 
Spec's. M.C. Z. No. Locality. Received from. 
1 18540 Isle au Haute, Me. M. C. Z. 
1 48207 Munsonville, N. H. J. Henry Blake. 
1 48217 Mt. Monadnock, N.H. Dr. W. H. Dall. 
2 42145 Duxbury, Mass. M. C. Z. (shell not 
found in one). 
1 48212 Tannersville, N. Y. Dr. H. A. Pilsbry, 
18 48211 Hudson, Ohio. Dr. R. C. Rush. 
2 48214 York Furnace, Pa. Dr. H. A. Pilsbry. 
2 48213 York Co., Pa. Dr. H. A. Pilsbry. 
4 48215 Wyoming Co., Pa. Dr. H. A. Pilsbry, 
This species was originally described as Limaz carolinianus 
(Bose, Hist. Nat. des Vers, suites 4 Buffon, ed Deterville, 1, 
p. 80, pl. 3, f. 1, 1802. Rafinesque (Annals of Nature, p. 10, 
1820) gave the name of Philomycus to species which differed 
from Limaz, principally, in being entirely destitute of a mantle. 
Rafinesque, however, made no mention of Limaz carolinianus in 
this paper and it remained for Ferussac (Tab. Syst., p. 15, 
1821) to place the species, which he spells caroliniensis, in Rafin- 
esque’s genus Philomycus. Binney (Bost. Journ. Nat. Hist., 4, 
p. 168, 1842), recognizing the fact that carolinianus Bosc. pos- 
sessed a mantle covering the entire upper surface of the animal, 
removed the species from Rafinesque’s genus Philomycus, where 
Ferussac had placed it, and made it the type of a new genus, 
