Page:Land Mollusca of North America (north of Mexico) Vol. I Part 1 277-end.pdf/136

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412 PILSBRY — NORTH AMERICAN

not appear to me to be pleurodontid, but better material is needed for an estimate of its place.

C. T. Simpson liberated specimens of the Cuban Zachrysia auricoma and Pleurodonte marginella, with other Cuban snails, in his place at Little River, Florida, at the north end of Biscayne Bay (Nautilus, 1919, 32: 104). I do not know that any still survive.

In the Recent fauna of our mountain and Pacific states this group is represented by two strongly characterized subfamilies, which have the following characters in common:

Shell umbilicate, with the outer and basal margins of the lip not expanded or reflected; penis without a verge; spermathecal duct long; talon exposed; kidney short or medium; jaw striate or plaited, not ribbed; marginal teeth bicuspid (cusps rarely notched).

And the following differential characters:

Ammonitellinae: Shell discoidal, one-colored, with somewhat zonitid texture, the periphery rounded at all stages of growth. An accessory sac arises at junction of vagina and oviduct; the talon is very long.

Oreohelicinae: Shell depressed to pyramidal, opaque, dull or with little gloss, banded or plain, striate or roughly sculptured, the periphery carinate or angular in immature stages. No accessory sac on vagina or free oviduct; talon simple, of moderate size.

Subfamily Oreohelicinae new subfamily

OREOHELIX Pilsbry

Oreohelix Pilsbry, 1904, Nautilus, 17: 131; 1905. Proc. Acad. Nat. Sci. Phila., p. 268 (type Helix strigosa Gld.); 1916, p. 340; 1917, p. 42; 1934, 85: 383 (anatomy and catalogue).—Henderson and Daniels, 1916, Proc. Acad. Nat. Sci. Phila.. p. 315; 1917, p. 49.—Henderson. 1918, Proc. Malac. Soc. Lond., 13; 21; 1924. Univ. Colo. Studies. 13: 109; 1936, 23: 87.
Helix, Patula and Pyramidula of some authors.

The shell is umbilicate, usually depressed but varying from discoidal to pyramidal, of 4 to 6 tubular or carinate whorls; earthy, with thin periostracum or none (except in subg. Radiocentrum); typically two-banded (but with many bands to none); embryonic whorls carinate, with radial striae or riblets and usually some spiral sculpture; neanic stage with the periphery angular or carinate. Aperture rounded or angular, toothless, the peristome blunt or sharp, the columellar margin dilated, lip otherwise not expanded or reflected.

The sole is undivided, foot granulose, with a pair of dorsal furrows and usually a distinct genital groove; tail depressed. Lung with venation chiefly on the cardiac side. Kidney short, little longer than the pericardium; secondary ureter closed throughout.

Genitalia (Figs. 277, 282). Penis rather large, truncate posteriorly, containing no verge or distinct papilla; epiphallus well developed, the vas deferens either terminal or inserted sublaterally on the convex end (which represents a flagellum). The vagina is rather long. Spermatheca globose, on a long duct. The talon is a rather large, curved sac, usually pigmented.Generated on 2012-11-10 02:35 GMT / http://hdl.handle.net/2027/uc1.31822013176466 Public Domain, Google-digitized / http://www.hathitrust.org/access_use#pd-google