HYALINIA FULVA CHERSINA. 127 
Kentucky—(H. A. Pilsbry). 
Maine—Orono, and a very fragile form at Kennebunkport, in company with 
H, fulva, and about equally common (G. H. Clapp). 
Massachusetts— Amherst (G. H. € lapp). 
Michigan —Not as common as typical fudva, but ranging widely over the state, 
and has been noted by Mr. B. Walker from nineteen of the eighty-four counties 
into which the state is divided. 
Minnesota—White Earth Lake and Thief River Falls (G. H. Clapp). 
Nebraska —Omaha, Roca, and Monroe Canyon, Sioux co, (G. H. Clapp). 
New Hampshire—((G. H. Clapp). 
New York—Lichfield and Westchester co. (G. TH. Clapp). 
Ohio— Cincinnati (G. H. Clapp). 
Pennsylvania—Edveworth (G. H. Clapp). 
Rhode Island—(H. A. Pilsbry). 
Tennessee—(H. A. Pilsbry). 
Vermont—Hartland (G. H. Clapp). 
In British North America it is recorded from Ottawa, Hamilton, Lake Rousseau, 
and Georeian Bay in Ontario. 
Var. trochula Reinhardt. 
Euconulus trochulus Reinhardt, SB. Ges. Naturf. Freunde Berlin, 1883, p. 43. 
Conulus chersinus trochulus Pilsbry, Nautilus, 1899, p. 116. 
Described as resembling chersina, but as paler in colour, less elevated (thoueh 
still high) and the crescentic aperture narrower. Diam. 2’8 mill. ; alt. 2°75 mill. 
Though near chersine this form, which links the true chersina with fulva, is said 
to be not difficult to distinguish, and may form a south-western racial group. 
Louisiana—On the north-west of the state (H. A. Pilsbry). 
Texas—Very abundant, New Braunfels (Pilsbry, Naut., Feb. 1899, p. 116). 
Var. dentata Sterki. 
Conulus Julvus var. dentata Sterki, Nautilus, May 1893, p. 45. 
Conulus chersinus dentatus Pilsbry, Nautilus, Feb. 1899, p. 117. 
Described as possessing at somewhat irregular intervals on the inner base of the 
last whorl a series of small and white, radially-disposed testaceous deposits, each 
with one to three prominences or teeth of exactly the same character as those of 
Gastrodonta lamellidens, and visible outwardly as white radiate markings, and 
possibly constituting defensive barriers. 
This peenliar armature of the mouth is practically restricted to young and 
adolescent individuals, and has been viewed as a character in process of acquire- 
ment by the species, tending also to bring it into harmony with the prevalence of 
similar structures existing amongst many diverse species living in the regions 
where it has been found. 
A consideration of the subject, however, leads to the view that this peculiarity 
is not nascent, but vestigial, and the survival of an ancient characteristic ; which 
is rendered probable not merely by the finding of this form only in the primitive 
regions of North America, but by the transient development of this strueture in 
young shells and its disappearance in adult life, thus recalling the recapitulation 
theory of the embryologists ; and the corroborative evidence of its living in Alabama 
in the less favourable hilly districts, while in the valleys the specimens exhibited 
no trace of this calcification, either in old or young shells. 
A parallel phenomenon exists in Pupa umbilicata or eylindracea, which exhibits 
in the young state a similar series of calcified radial processes, all of which 
disappear before the maturity of the shell. 
According to Pilsbry, it is a very rare form, and oceurs cabal 
Alabama—In many localities, Jackson co., H. E. Sargent (Sterki, Nant., l.c.). 
Arkansas—Logan co. (H. A. Pilsbry). 
Columbia— Washington, E. Lelinert. 
Ohio—In several localities around Cincinnati (Doherty, Quart. Journ. of Conch., 
1878, i., p. 344). 
Virginia—(G. H. Clapp). 
