[687] INVERTEBRATE ANIMALS OF VINEYARD SOUND, ETC. 393 
aves). Greenland (Méreh). Labrador, 15 to 50 fathoms, (Packard). Fos- 
sil in the Post-Pliocene at Montreal, rare, (Dawson); Brunswick, Maine 
(Packard). 
Possibly some of the Gulf of Saint Lawrence specimens may belong 
to the following species. 
CRYPTODON OBESUS Verrill. Plate XXIX, fig. 214. (p. 509.) 
American Journ. Science, vol. iii, pp. 211, 287, Plate 7, fig. 2, 1872. 
Shell white, irregularly and rather coarsely concentrically striated, 
much swollen in the middle; the transverse diameter nearly equal to 
the length; the height considerably exceeding the length. The beaks 
are prolonged and turned strongly to the anterior side. The lunular 
area is rather large and sunken, somewhat flat, in some cases separated 
by a slight ridge into an inner and an outer portion. Anterior border 
with a prominent rounded angle; ventral margin prolonged and round- 
ed in the middle; posterior side with two strongly-developed flexures, 
separated by deep grooves. Interior of shell with radiating grooves, 
most conspicuous toward the ventral edge. 
Length of the largest specimen, 15™™; height, 18™"; thickness, 15™™. 
The smaller specimens have about the same proportions. 
Six single valves, some of them quite fresh, were obtained off No- 
man’s Land at different localities. They were all right valves, and the 
smallest was 12.5" of an inch in height. The specimen from Labrador 
agrees nearly-in form and structure, and is only 5.75™™ in height and 
5™™ in length. 
This species'appears to be more neatly related to C. fleruosus of Eu- 
rope than to C. Gouldii. The European species is nearly intermediate 
between the two American shells in form; but judging from the speci- 
mens that I have had opportunities to examine, the three forms ought 
to be kept distinct. C. Gouldii is a thinner and more delicate shell, 
more rounded, relatively much longer, and is seldom more than 6™" to 
7" in breadth. 
Block Island to Labrador. East of Block Island, in 29 fathoms, fine 
sandy mud; off Gay Head, 19 fathoms, mud; Casco Bay, 60 fathoms, 
mud. Labrador (Packard). East of Saint George’s Bank, 430 fath- 
oms (S. I. Smith). 
Turtonia minuta Stimpson. 
Shells of New England, p. 16, 1851 (non Alder, Forbes and Hanley, ete.); Gould, 
Invert., ed. ii, p. 85, fig. 395. Venus minuta Fabricius, Fauna Grinlandica, p. 
412, 1780. Turtonia nitida Verrill, Amer. Journ. of Sci. vol. iii, p. 286, Plate 7, 
figs. 4, 4a, 1872. 
Massachusetts Bay to Greenland. Common under stones and in rocky 
pools at low-water, in Massachusetts Bay and Casco Bay. Although 
this species has not yet been found south of Cape Cod, so far as I am 
aware, it will probably be found hereafter on the more exposed rocky 
shores, as at Point Judith, Watch Hill, or on some of the outer islands. 
