ae 
240 HELIX ASPERSA. 
The GYPSOBELUM or love-dart is eight to ten millimetres in length, and though 
soft and flexible when removed from the sac, hardens quickly on exposure; it has 
a caleareous, hollow, slightly-eurved, ant pointed stem, somewhat expanded at 
the base, which fits upon and is slightly attached to the distal tubercle at the 
base of the sac, and is strengthened by four projecting, longitudinal blades, placed 
at right angles to each other, with somewhat thickened and rounded though slightly 
twisted outer edges, which cause the dart to revolve slightly during protrusion ; 
Fic. 312. Fic. 313. Fic. 314. 
Fic. 312.—Gypsobelum or Love-Dart of Helix aspersa, X 4, Christchurch, Hants. 
Fic. 313.—An unusually ramose digitate macus gland of /Yedix asfersa, bearing 46 branchlets, x 2. 
Fic. 314.—A very sparsely digitate mucus gland, with 14 branchlets only, x 2. 
the blades gradually diminish towards the point, but more abruptly basally, and 
are connected together at intervals by four to twelve crescentic and very thin 
ealeareous films. The number of longitudinal blales is, however, not absolutely 
invariable, and specimens have been found possessing only two, the opposite pair 
having remained undeveloped. 
The dart of this species belongs t» a type whose characteristics are shared by 
only one other British species, H. nemoralis. 
The ALIMENTARY SYSTEM is of the usual triodromous! character ; the thin-walled 
(ESOPHAGUS leads to the distensible elongate Crop, which is strongly ridged 
internally ; the whitish SALIVARY GLANDS on its outer walls pour their secretion 
into the BUCCAL CAVITY hy a p.ir of long and slender DUCTS ; beyond the crop, the 
Fic. 315.—Alimentary canal of He/ix asfersa, with appended glands, showing the regional division 
of its tracts (modified after Howes). 
fe. fore-gut or anterior region of the alimentary tract 3 #.g. mid-gut or stomachal region, and 4.g. 
hind-gut or intestinal region; 4.c. buccal cavity, showing radula, radula sac and jaw; cr. crop; _/. foot; 
g ; y, sl g radu je 
A.g. hermaphrodite gland or ovotestis; ¢.2. anterior lobe of liver; @. cesophagus 5 f.g. pedal gland ; 
pr. pharyngeal or buccal retractor; ». rectum ; .¢. posterior lobe of liver; s.d@. salivary duct ; s.g. 
salivary glands; st. stomach; ¢y. typhlosole. 
alimentary tract contracts, but at the end of the ingestive tract abruptly enlarges, 
and forms a sacculate STOMACH, whose lining membrane is thrown into many 
longitudinal ridges, the ducts from the right and left lobes of the large and impor- 
tant DIGESTIVE GLANDS entering separately ; on leaving the stomach the IN'TEs- 
TINAL CANAL is directed forwards, and forms the first tract of its course, keeping 
to the left side of the body and within the tissues of the LIVER; on the termination 
of the first tract the canal is looped by and held in position by the anterior aorta ; 
the second intestinal tract is directed towards the rear, and crosses to the right side 
of the body and becomes more dorsal in position ; the final tract or RECTUM, which 
is again directed forwards, travels along the margin of the lung beneath the 
URRETER and opens on the posterior side of the PULMONARY APERTURE. 
1 Monog. i., p. 284. 
