ISOPODA. 
235 
are veiy small and entirely inferior. The antennae consist of nine 
joints, the last four composing the stem. On each side is a depressed 
tubercle representing one of the intermediate antennae ; the interven- 
ing space is raised. The branchiae are vesicular, imbricated, and 
covered by laminae *. 
Ligia, Fab. 
The stem of the lateral antennae composed of a great number of 
small joints ; two very salient stylets divided at the end into two 
branches, at the posterior extremity of the body. 
Ligia oceanica ; Oniscus oceanicus, L., Desmar., Consid., 
XLIX, 3, 4, about an inch long, grey, with two large yellowish 
spots on the back. The lateral antennae are less than half the 
length of the body, and their stem consists of thirteen joints. 
The stylets are as long as the tail. This animal is very common 
on the coast of France, where it is seen climbing up the rocks, &c. 
If an attempt be made to capture it, it quickly folds up its feet 
and lets itself fall. 
In the Ligia italica, Fab., the lateral antennae 'are nearly as 
long as the body ; the sixth joint, or the stem, is divided into 
seventeen small ones. The stylets are much longer than the tail. 
Ligia muscorum; Oniscus hypnorum. Fab., Cuv., Journ. 
d’Hist. Nat. II, xxvi, 3, 4, 5 ; Oniscus agilis, Panz., Faun., Ins. 
Germ., Fascic. IX, xxiv. The lateral antennae shorter than the 
lialf of the body, and their stem composed of but ten small 
joints. The peduncle of the posterior stylets is furnished on the 
inner with a tooth and seta. 
In others, all terrestial, the lateral antennae consist at most of eight 
joints Avhich gradually diminish in size towards the extremity, so that 
no one of them appears to be divided or compound. 
Here, the posterior appendages, or stylets, project beyond the last 
segment. The body does not contract into a ball, or does it im- 
perfectly. 
Philoscia, Lat. 
The lateral antennae divided into eight parts and exposed at base ; 
the four posterior appendages nearly equal. They are only found in 
wet places f . 
Oniscus, Lin. 
The true Onisci have also eight joints in their lateral antennae, 
but their base is covered, and the two external appedages of the 
extremity of the tail are much larger than the others. These animals 
and those of the two following subgenera are vulgarly called Clous- 
a-porte, and by syncope Cloporte, Porcelets de Saint-Antoine (a). 
* Tylos armadillo, Lat., fig, in the pi. d’Hist. Nat. of the great work on Egypt — 
from the Mediterranean. 
f Oniscns sylcesfris, Fah. ; Oniscus muscorum, Cuv., Journ. d’Hist. Nat. II, xxvi, 
6, 8 ; Coqueb., Ill, leon. Inseet., Dec. I, vi, 12. 
{a)These “ Pigs of Sf. Anthony" are American Wood-Lice — Boiled in milk they 
still constitute a favourite remedy with numerous patients, and some few equally|intelli- 
gent practitioners, who attribute to them diuretic, absorbent, and aperient qualities. 
That they may act as an emetic, I can readily admit. — E ng. Ed. 
