ORDER STOMAl’ODA. 
109 
body, enclosing a good part of the heart, and serving as an 
attachment for the respiratory organs, cannot, considering this 
relation, he assimilated to that portion of the body termed 
tail in the decapods ; it is an abdomen, properly so called. 
Its last segment but one has, on each side, a fin, similarly 
composed as that of the tail in the macrouri, but often armed, 
as well as the last segment or intermediate piece, with spines 
or teeth. 
We shall divide the stomapods into two families; in the 
first, that of 
Untpeltata, 
The testa forms but a single buckler, in the shape of an elon- 
gated quadrilateral figure, usually widened, and free behind, 
covering the head, with the exception of the eyes and antennae 
(which are borne on a common and anterior articulation), and 
the first segments at least of the thorax. Its anterior extre- 
mity is terminated in a point, or is preceded by a small plate, 
finishing in a similar manner. All the jaw-feet, the second 
of which are very large, and the four anterior feet, are very 
much approximated to the mouth, on two lines, converging, 
inferiorly, and are formed like claws, with a single finger or 
hook, mobile and folded. If we except the second feet, all 
these organs have, externally, at their origin, a small pedi- 
cled bladder. The other feet, six in number, and the third 
articulation of which carries laterally and at its base an ap- 
pendage, are linear, terminated by a brush, and simply nata- 
tory. The lateral antennae have a scale at their base, and the 
stem of the intermediate is formed of three threads. The 
body is narrow and elongated, and the ocular peduncles are 
always short. 
This family is composed of a single genus, that of 
Squilla, Fab., 
Which we thus divide : 
