20 HYGROMIA HISPIDA. 
able that these auxiliary and empty sacs in the present and certain other species 
represent the coronal glands present in Zonitoides. 
Fie. 31. Fic. 32. Fic. 33. 
Fic. 31.—Dart sacs and mucus glands of Hygromia hispida, greatly enlarged (after Ashford). 
Fic. 32.— Diagram showing the paired arrangement of the vaginal mucus glands (after Ashford). 
Fic. 33.—Darts of Hygromia hispida, showing the curved and straight form of dart, x 24. 
The GYPSOBELA or love-darts are two in number, about 0°75 mill. in length, of a 
crystalline white, and usually curved or awl-shaped, though occasionally straight, 
with a slender, smooth, and tapering shaft, and a comparatively bulky base, with 
only occasionally slight indications of an annulus. 
JAW strongly arcuate, with an indistinct blunt median rostrum or beak, and 
showing numerous flattish ribs on the anterior surface, which are rendered strikingly 
perceptible by their distinct 
and apparently grooved 
lines of demarcation ; 
there are also several sub- 
sidiary intermediate lines; 
the jaw is of a deep amber 
colour, darker along the 
lower or cutting margin, ; ? 
but deepest in the central Fic. 34. Fic. 35. 
area, indicating the line of Fic. 34.—Jaw of H/. hispida U.. (the i. concinna of Jeffreys) 
attachment of the buccal x 30 (after micro-photograph by Mr. W. Bagshaw). 
ee et ray ; Fic. 35.—Jaw of H. Aispida var. hispidosa (the H. hispida of 
vee) Pe ones ane Jeffreys) x 30 (after micro-photograph by Mr. W. Bagshaw). 
gin 1s broadly crenulate, 
the indentations marking the limits of the plates of which the jaw is composed. 
The RADULA is of the usual oblong shape, and about 24 mill. long, and 1 mill. 
wide, with about 100 sinuately transverse rows of teeth, each row containing on the 
average about 61 teeth, composed of a short, almost quadrate, tricuspid median 
tooth, about 10 more or less obliquely quadrate bieuspidate laterals, of which the 
reflection gradually becomes more slender and elongate as the teeth recede from 
re eRe 
Fic. 36.—Representative denticles from the radula of Hygromia hispida, collected by Major 
3arrett-Hamilton at Kilmanock, Wexford, and photographed by Mr. Walter Bagshaw, from a 
preparation by Mr. J. W. Neville (highly magnified). 
the centre and approximating somewhat to the marginals, which are about twenty 
in number, distinguished by their diminished basal plates and relatively enormous 
cutting points; the marginals, though at first bifid and not greatly different in size, 
become rapidly reduced in their dimensions, and trifid or even quadrifid as they 
approach the outer margin of the radula. 
The formula of a Kilmanock specimen, collected by Major Barrett-Hamilton, is 
$9, +42 4+44 42 + 2% x 100=6,100 teeth. 
Reproduction and Development.— Nothing has been hitherto noted 
in reference to the details of sexual congress in this species, but it is known 
that this may take place during mild weather throughout the season and 
may occur even before the maturity of the shell. 
