58 HYALINIA ALLIARIA. 
That the species of the restricted” group Huhyalinia should display a 
close affimty in their shells and general aspect, as well as present con- 
siderable conformity in their internal organization is quite naturally 
to be expected, and though there are ample and constant differences to 
justify the separation of the various recognised species, yet the general 
proportion and character of the different parts, as the direct course of the 
hermaphrodite duct; the position of the spermatheca and the length, 
tapering form, and peculiar flexure of its stem; the marked bending of 
the free oviduct; the form, position, and nature of the vaginal gland, 
and other characteristic peculiarities, make it abundantly evident that 
though the different species have undoubtedly finally parted company, they 
have not yet greatly diverged from a common ancestral type. 
H. alliaria shows its individuality by the deep pigmentation of the 
animal extending even to the most remote internal parts ; by the smell 
of garlic, from which its trivial name is derived, being so intense and 
permeating, and by the mantle margin constantly showing much slighter 
pigmentation than in //. helvetica ; “put what should weigh most heavily 
in the scale is the fact that these little shells of adliari ia, barely six 
mill. in diameter, always contain sexually mature animals clearly exhibit- 
ing the characters of the species ; while if specimens of HZ. cellaria or 
H1. helvetica of the same size be examined, the reproductive organs in 
every case are quite rudimentary and undeveloped, and it is not until 
the shell becomes much larger and full growth nearly attained that these 
organs are perfected. 
Diagnosis.—The sHeLt of H. alliaria differs from that of H. celluria 
in its smaller size, darker colour, greater convexity and thickness; the 
mouth also is less oblique, and the whitish basal opacity not so apparent ; 
it has also one whorl less, and a more open umbilicus. From H. helvetica 
it is distinguished by its much smaller size and its much wider umbilicus, 
‘he ANIMAL is characterized by its dark coloration, a feature also dis- 
tinguishing /7. lucida, differing thus from the much paler animals of 
FH. cellaria and H. helvetica. It is also remarkable for its much greater 
power of exhaling the odour of garlic when annoyed or injured. ‘The tail 
is short and only extends just beyond the shell during locomotion, con- 
trary to what obtains in its close ally H/. helvetica. 
INTERNALLY, this species is strongly differentiated by the dark pigmen- 
tation of the body, which extends to more distant parts than in the 
kindred species, as the intestines, the oviduct, and the anterior portion of 
the esophagus are all more or less affected; the somewhat globose sperma- 
theca, the annulation around the base of the penis-sheath, and the absence 
of the milk-white arterioles of the liver, which are so conspicuous in /7. 
helvetica, are also striking points of divergence. 
Original Description.—‘‘37 Helix alliaria (nobis). Spec. char. : An umbilicated, 
depressed, pellucid, horn-coloured shell, having no more than four volutions. 
Observation : This species never arrives to the size of H. nitens, has one volution 
less, and is found under moss on old trees. Its inhabitant smells strongly of 
garlick.”—J. 8. MILLER, Annals of Phil., May 1822, iii., p. 379. 
Description.— ANIMAL with body rounded in front, with short and pointed 
TAIL, scarcely extending beyond the shell during locomotion ; the BODY is of a 
slaty blue-black above, darkest towards the head, the deep piginentation is bounded 
below by the LATERAL GROOVES, which extend from the RESPIRATORY ORIFICE to 
beneath the LOWER TENTACLE on the right side of the body, and occupies a similar 
position on the left side of the body ; the two DORSAL GROOVES are distinct and 
