CHIROCEPHALUS. 53 



On the lOtli, at six p. m., ninety-six hours after birth, 

 it had become somewhat increased in length. The knobs 

 were nine in nnmber, the four uppermost being free from 

 the body, and setiferous at the extremity, and much in- 

 creased in length. The antennae had diminished in length 

 in proportion to the body. 



On the 11th, seven p. m., about 120 hours after birth, 

 I found it had undergone scarcely any change in ap- 

 pearance. 



On the 12th, 144 hom-s after birth, I found it en- 

 veloped in a covering of filmy, slimy stuff, w^hich had 

 been floating about in the water. It had, notwithstand- 

 ing, gone on increasing in development. The knobs were 

 eleven in number ; the first six pairs free, and the three 

 or four superior pairs distinctly lamellar. The lateral 

 eyes had become distinctly pedicled, and on each side of 

 the median eye there was a slight projection or knob. 

 I was unfortunately prevented carrying my observations 

 further. 



The female begins to lay before she has attained her 

 full size, and lays several times during the season. Each 

 time the ova are transmitted from the internal to the ex- 

 ternal ovary, the animal throws off its skin. 



1. Chirocephalus diaphanus. Tab. Ill, figs. 1, 2. 



Chihocephalus diaphanus, Prevost, Jouru. dePhys., 1803, Ivii, 37, 



1. 1, f. 1-3. 

 — Jurine, Hist. Monoc, 201, t. 20-22. 



Bkanchifus Pkevostii, Fischer, Bull. Soc. Imp. Nat. Moscou, 



vii, 1834. 

 CnifiocEPHALUS Prevostii, Thompson, Zool. Research., fasc. vii, t. 3, 



f. 4, 5 ; t. 4, f. 1, 1834. 

 Bkanchifus chibocephaxus, Guerin, loon. Reg. An. Crust., t. 33, f. 3. 

 Bhanchipus DIAPHANUS, M. Edwards, Hist. Crust., iii, 368. 

 BfiANCHiPUS PALUDOSUS, Desmarest, Cousid. geu. Crust., 389, t.5G,f.2. 

 — Lamarck, Hist. An. s. Vert., 2d. edit., 



V, 198. 



