STOMAPODA. 
211 
the lateral part of the abdomen, reach the anterior margin of the pre- 
ceding ring, and terminate on the superior surface of the heart near 
the median line, one partly mounting on the other. The medullary 
cord, exclusive of the brain, presents but ten ganglions, of which the 
anterior furnishes nerves to the mouth ; the three following, those 
of the six natatory feet, and the last six, those of the tail. Thus, 
although the four last foot-jaws represent the four anterior feet 
of the Decapoda, they nevertheless form a part of the organs of man- 
ducation. The stomach of these Crustacea — Squillae — is small and 
has but a few very small teeth* near the pylorus. It is followed by a 
straight and slender intestine which extends along the whole abdo- 
men, accompanied on the right and left by glandular lobes, which 
appear to supply the want of a liver. A ramous ai^pendage adhering 
to the inner base of the last pair of feet appears to characterize the 
male. 
The teguments of the Stomapoda are thin, and, in several, nearly 
membranous or diaphanous. The shell is sometimes formed of two 
shields, of which the anterior corresponds to the head, and the pos- 
terior to the thorax, and sometimes of a single piece, which however 
is free behind, usually exposing the thoracic segments, bearing the 
three last pairs of feet, and having an articulation before that serves 
as a base to the eyes and intermediate antennae ; these latter organs 
are always extended and terminated by two or tlu’ee threads. The 
eyes are always approximated. The formation of the mouth is 
essentially the same as in the Decapoda ; but the palpi of the mandi- 
bles, instead of being laid on them, are always vertical. The foot- 
jaws are deprived of the flagelliform appendage presented to us by the 
same i^arts in the Decapoda. They have the form of claws, or of 
small feet, and, at least in several — the Squillae, — their external base 
as Avell as that of the two anterior feet properly so called, exhibits a 
vesicular body. Those of the second pair, in the same Stomapoda, are 
much larger than the others, and even than the feet, which has caused 
them to be considered as true feet; fourteen of them have been 
counted f. I’he four anterior feet have also the form of claws, but 
are terminated as well as the foot-jaws by a hook which curves to- 
wards the head, on the inferior and anterior edge of the preceding 
joint or of the hand. In others however — the Phyllosoma for instance^ 
* They form two ranges of transverse and parallel striae. 
i* The second jaws of these Stomapoda no longer present the same form as those 
of the Decapoda. They have the figure of an elongated triangle divided into four 
segments by transverse lines. The mandibles are bifurcated and well dentated. 
J In all those where the four anterior feet are in the form of claws, the six last 
are natatory. 
p 2 
