HYGROMIA FUSCA. 49 
obovate, abruptly flexed and bluish-white in colour, with longitudinal white streaks 
at the narrowing distal end; EPIPHALLUS long, of an uniform thickness and furnished 
with a retractor about midway of its course; the FLAGELLUM is long and filiform. 
Fic. 70. Fic. 71. Hic: 725 BIGs ics 
Fic. 70.—Dart-sac of Hygromia fusca (showing position of the dart within the sac), accessory sac 
and digitate mucus glands, greatly enlarged. 
Fic. 71.—Reproductive organs of Hygromia fusca, greatly enlarged. 
d.s. dart-sac and accessory gland; 77. flagellum ; 77.¢7. mucus-glands ; ov. oviduct; #.s. penis- 
sheath ; 7. penial retractor; sf. spermatheca; sf.d. sperm duct. 
Fic. 72.—Gypsobelum or Love-dart of Hygvomeia fusca, with mid-section of stem, x 12. 
Fic. 73.—Ovotestis imbedded in the digestive gland of an immature H. fusca, greatly enlarged. 
The vaginal MUCUS GLANDS are three or four mill. in length, and bluish-white 
in colour, subulately vermiform and irregularly tumid; they are usually seven to 
nine in number, though somewhat variable in this respect, as by bifurcation there 
may be as many as twelve or even more terminations. 
DART-SAC pearly-white, elongately ovate, and fairly bulky, combined with a 
smaller accessory glandular sac or lobe, which rises a little higher, and fused to the 
vagina on almost the total length of the gland ; the outer sac contains and secretes 
the dart. 
The DART occupies the large outer sac or lobe, is of a subulate shape, about two 
mill. long, very sharply pointed, the shaft gracefully bent, with four equidistant 
longitudinal blunt-edged blades, which arise from the expanded base, and gradu- 
ally diminish towards the apex, quite reminiscent of that of Helix pomatia ; the 
swollen base oceupies about one-fourth of the total length of the dart and expands 
somewhat abruptly from the gently tapering shaft; there is no annulus, but there 
are usually one or more horizontal encircling grooves. 
The JAW is about three-quarters of a millimetre from side to side, of a fawn or 
deep amber colour, darker in the central area and towards 
the cutting-edge, of a ecrescentie shape, with bluntly 
rounded ends, with twenty to twenty-eight not very prom- 
inent ribs which crenulate the cutting margin. 
Moquin-Tandon describes the jaw as possessing fifteen wy q 
fine closely-set indentations on the concave cutting mar- Fic. 74.— Jaw of H. fusca, 
gin, and figures it as very broad, with a very wide and (Montagu) highly magnified, 
obtuse but quite perceptible median rostrum or beak. from Scarbro’, Yorks. 
The RADULA is of the usual oblong shape, and composed of 95 transverse rows of 
teeth, with a maximum of about 53 teeth in a row, each row formed by a median 
Fic. 75.—Radula of Hygromia fusca collected at Huddersfield by Mr. Lister Peace, from a 
highly magnified micro-photograph by Mr. W. Bagshaw of a preparation by Rey. Prof. Gwatkin. 
9/9/16 D 
