276 BULLIDZ. 
disk, and not very close together; they are black, and sessile 
in the centre of a minute circular lucid spot: M. Cuvier has 
overlooked them. The fissure of the mouth is vertical; this 
is placed in the centre and between the tentacular and pedal 
disks; and on each side the mouth, within the groove, are 
two elegant conspicuous leaflets perfectly symmetrical, each 
consisting of twenty strands on each side the stem, which are 
largest posteriorly, and gradually diminish until they are lost 
at some little distance from the buccal orifice by suddenly 
turning inwards, appearing to pierce the groove and enter the 
buccal cavity ; they are light yellow; the one on the right side 
is placed just above the seminal groove, the other on the left 
in a symmetrical position; the strands under the microscope 
appear to be glandular, without a leading vein or artery ; they 
have the aspect of minute, wiry, dendroid filaments. These 
organs I should have taken for the salivary glands, if M. Cuvier 
had not stated the presence of others of a strap-shaped form 
in another place, and as he has given nearly a similar form to 
the salivary glands of the Aplysia, Helix aspersa, and other 
hermaphrodites, I must defer to such authority. I will return 
to this pomt. I have now described all that can be seen 
without dissection. 
The vertical fissure of the mouth is faced by the anterior 
part of the tongue, which consists of two hemispherical por- 
tions, each furnished with fifteen obliquely arcuated yellow, 
wiry, horny strands, set with short transverse hooks bending 
posteriorly. This denticular apparatus does not extend through 
the large, oval, pale red fleshy buccal mass, and is not sup- 
ported by distinct corneous plates, but by a tough coriaceous 
membrane. From the posterior end of the buccal mass the 
cesophagus proceeds straight to the gizzard; it is long, flat, 
broad and dilatable, accompanied by the two straps described 
by M.Cuvier as the salivary glands, which are fixed to each side 
of the anterior and upper part of the gizzard, and run on each 
side the cesophagus to the posterior end of the buccal mass, to 
which also on each side they are attached, apparently only to 
the external surface, and do not appear to pierce it. Under 
the microscope they have little appearance of being glandular 
