6 HYGROMIA STRIOLATA. 
opaque white or buff cores, while each digitation is joined to the oviduet by a short 
slender stalk. The PENIS-SHEATH is very stout and white in colour, but distinetly 
constricted at its junetion with the ATRIUM, where it is smeared and spotted with 
brown; the distal end is continued as a tapering and twisted EPIPHALLUS, to 
which is aflixed a broad RETRACTOR MUSCLE, and the terminal FLAGELLUM is also 
well developed. 
The STYLOPHORES or true dart-sacs 
are two in number, of a semi-transparent 
white or yellowish-white colour, finely 
spotted with brown, and are placed on 
opposite sides of the vagina, each asso- 
ciated with a smaller, more opaque, and 
empty superimposed auxiliary sac or lobe 
of similar external aspect. 
The GYPSOBELA or twin love-darts are 
more than a millimetre in length, and Fic. 15. Fic. 16. 
usually slightly curved, but sometimes Fic. 15.—Gypsobela or Love-darts of Hygro- 
are perfectly straight, with a tapering, mia striolata, X 20, 
Fic. 16.—Apex of the Love-dart of //. str7o- 
fata, to show the initiation or incipient forma- 
tion of the lateral blades (greatly enlarged). 
round and smooth hollow shaft, and a 
relatively large and expanded base of 
attachment, which shows obscure traces 
of an annulus, and also a noticeable tendency to develop a pair of longitudinal 
blades at the apex. 
The ALIMENTARY SYSTEM is on the general Helicidian plan; the SALIVARY 
GLANDS are long and narrow, of a slaty-grey colour, with darker ducts, but in 
comparison with Helix aspersa, differ in surrounding the middle of the cesophagus, 
and not clasping the crop; the GiSOPHAGUS also is longer in proportion, and leads 
to the voluminous light brown or buff coloured Crop, which, as is usual, merges 
into the STOMACH, Whose position is often displayed by a more pronounced disten- 
sion, and by the place of entry of the bile ducts; the GUT is of the ordinary trio- 
dromous character, but the yellowish-white intestinal flexures contrast strongly 
with the dark coloured LIVER, and are more distant from the posterior end of the 
stomach than in that species. 
The JAW or mandible is crescentie in shape and of the aulacognathous or pyeno- 
gnathous type, and amber in colour, bearing on its 
anterior surface a broad and flat central and vertical 
rib, which perceptibly projects beyond the general 
outline, and numerous delicate lateral ribbings which 
only slightly crenulate the cutting margin; the line of 
attachment of the mandible to the buccal cavity is 
shown by the stronger and thicker medial region, FiG.17 Pe 
zt ’ : 1G. 17.—Mandible or Jaw of 
which appears as a darker area extending across the 77, s#;zo/ata, greatly enlarged 
mandible parallel to the cutting margin and as a (from a micro-photograph by 
posterior extension. Mr. W. Bagshaw). 
The RADULA is of the usual oblong form, and in the specimen figured possesses 
about 104 longitudinal rows of teeth, with a maximum of 67 teeth in a transverse 
row, each row being constituted by a somewhat long, narrow, and tricuspidate 
central tooth bearing a long and powerful median cutting-point or mesocone and 
two insignificant subsidiary eutting-points or ectocones placed far back at the 
shoulder of the tooth ; the laterals are uniformly bidentate and conspicuously larger 
than the median row; the mesocone also is larger and stronger, the endocone or 
J 
Fic. 18.—Representative denticles from half-a-transverse row of teeth of the radula of Wygromia 
striolata, from Kilmanock, Wexford, collected by Major Barrett-Hamilton (from a highly magnified 
micro-photograph by Mr. W. Bagshaw of a preparation by Mr. J. W. Neville). 
inner cutting-point becomes entirely lost or suppressed, but the ectocone or outer 
entting-point 1s retained and gradually increases in size and strength as the teeth 
recede from the centre; about the twentieth row the splitting of the ectocone 
