604 CEASS xX, 
insects. In Oniscus and Porabea, according to 'TREVIRANUS, four 
short vessels, which open into the rectum close to its extremity, 
may perhaps correspond to the urinary vessels, or, as he supposes, 
to the biliary, although they differ from them greatly by their 
shortness}. As little are salivary organs known hitherto, except 
in the Cirripedia. The liver, onthe contrary, is commonly much 
developed here. In some lower crustaceans the intestinal canal is 
surrounded by a layer of small blind sacs (follicul’) or glandules, 
which may be regarded as a liver intimately connected with the 
intestine. In the Cirripedia the intestine below the stomach is 
surrounded by a liver formed of many blind sacs. In the Oniscides 
from two to six long blind liver-tubes are found, in most of the 
genera four, often with dilations like a string of beads, which are 
described by some writers as the adipose body of these animals. 
In Bopyrus the intestinal canal, according to RaTuKs, receives 
seven liver-tubes on each side, which lie behind each other in the 
length, an arrangement which recalls that in the scorpions, whilst 
besides an unpaired liver-mass, incised into three parts, lies in front 
of the others on the stomach?. In Limulus there are two very wide 
gall-ducts on each side, at some distance behind the pylorus ; they 
receive the blind convoluted tubes, of which the large liver-mass of 
this animal consists. In the decapod crustaceans only one gall- 
duct is found on each side, terminating in the intestinal canal, be- 
hind the lower orifice of the stomach. The liver is a double and 
symmetrical organ, as in most crustaceans, and each liver is divided 
more or less distinctly into three lobes; in each of these lobes runs 
a tube, that terminates in the common gall-duct, and round about 
the tubes blind sacs (follicul’) are set, which unite as fingers do. 
These follicles consist of three membranes, of which the internal 
and external present no special structure; the external is more con- 
sistent and more intimately connected with the middle membrane. 
1 Verm. Schr. 1. s. 58, Taf. vit. fig. 38, i. g. 
2 In Squilla the liver consists of lateral blind sacs divided into branches that 
extend throughout the whole intestinal canal, a disposition which agrees with that in 
Bopyrus, and may also be compared with that in Aphrodita (see above, p. 211). 
Above the liver, on the dorsal surface, lie the testes or ovaria, which also extend longi- 
tudinally, and consist of branched glandular lobes. The ovaria of Squilla were de- 
scribed by CuviER as liver. See Duvernoy Ann. des Sec. nat., 2e Série, Tom. VI. 
1836, pp. 247—251. 
