PiECILOPODA. !J69 



Some of them whose feet are free, and (the two last excepted) 

 annexed to the anterior part of the body — Cephalothorax, Lat. — 

 covered by the shield, in which some of the posterior feet are fur- 

 nished with numerous and pennated threads, and in which the siphon 

 is not apparent, have the abdomen naked above and terminated by 

 two long threads, or as many styles; they compose the subgenus. 



C MiiGvs, properli/ so called, — Calxgus risculus, Leach*. 

 In all others, the superior surface of the body is imbricated, or that 

 portion of the body is inclosed in a kind of case formed by the last 

 feet which resemble membranes and fold over it. 



Of these latter, there are some whose antennae never project like 

 little claws, whose feet are free, and whose last ones do not envelope 

 the body like a membranous case. They form the following sub- 

 genera. 



Pterygopoda. Lat. — Nogaus ? Leach. 



Where the posterior extremity of the body is terminated by two 

 kinds of fins; where the under part of the post abdomen or of the 

 second division of the body, not covered by the shield, is furnished 

 with pinnated or digitated feet ; and where there is a distinct pro- 

 boscis or rostrum f. 



Pandarus, Leach. 



Two threads at the posterior extremity of the body ; the first and 

 fifth pair of feet unguiculated, and the remainder digitated ; no ap- 

 parent siphon 1- 



DiNEMOURA, Lat. 



Two long anal filaments and an apparent siphon ; the two anterior 

 feet unguiculated'; the two following ones terminated by two long 

 toes, and the remainder membranous leaflets §. 



The last subgenus of this subdivision, that of 



Anthosoma, Leach, 



Approximates to Dinemoura in the presence of a siphon, and in 

 the two caudal threads ; but it is removed from it, as well as the pre- 

 ceding ones by its projecting antennae, which resemble little mono- 

 dactyle claws, and by its six last feet which are membranous, 



to conclude that these threads are a kind of external oviducts ; but is there no 

 mistake in this ? I have studied these same organs in various specimens — preserved 

 in spirits, it is true — but could never discover any body whatever. 



* Caligus piscinus, Lat.; Cat. mrtus, Miill. Entom. XXI, 1, 2; Monoculus pis- 

 cinus, L. ; Cat. MuUeri, Leach ; Desmar., Consid., L, 4; found on the Cod. The 

 Oniscus lufosits, Slabber, Encyclop. Method., Atl. d'Hist. Nat. CCCXXX,'?, 8, from 

 the fin-like appendages of its tail, seems to indicate a separate subgenus. The 

 Binode a queue en plumef, Geoff., might be placed in it. 



t A single living species found on the Shark. See the genus Nogaus, Desmar., 

 Consid., p. 340. 



X Pandarus bicolor, Leach; Desmar., L. 5; Pandarus Boscii, Leach, Encyc. Brit. 

 Suppl. 1, XX. For the other species, see Desmar., lb., p. 339. 



§ Caligtis productus, Miill., Entom. XXXI, 3, 4; Monoculus salmoneus, Fab. 



