TONE THORACICA. 



I SO POD A. 



NORMALIA. 



255 

 BOPYRIDJE. 



TONE THORACICA. 



Male. Narrow, subparallel, first segment of the body shorter than the 

 following, the remainder with the sides subangulated. 



Female. Pyriform, flattened, basal appendages of the tail multi-ramose. 

 Length of female, about one-quarter of an inch. 



Oniscus thoracicus. 



MONTAGU, Trans. Linn. Soc. ix. p. 103, pi. 5, f. 3. 



Oniscus (lone) thoracicus. LATREILLE, Enc. M6th. pi. 336, fig. 46. 



lone thoracicus. LATREiLLE,in Regne An.Ed. i. iii. p. 54. LAMARCK, 



Hist. Anim. sans Vertebres, v. p. 170. DESMA- 

 REST, Cons. Crust, p. 286, t. 46, f. 10. GUERIN 

 MENEVILLE, Icon. R. Anim. Crust, t. 62, 

 f. 1, 2. MILNE EDWARDS, Crust, iii. p. 280, 

 t. 33, f. 14, 15. CUVIER, Regne Anim. (Edit. 

 Crochard) Crust, t. 59, f. 1. WHITE, B. M. 

 Cat. Brit. Crust, p. 81. Pop. Hist. Brit. 

 Crust, p. 254, pi. xiv. f. 8a (male), b (female). 



IT is to Colonel Montagu that we are indebted for the 

 first knowledge of this interesting parasite, which inhabits 

 the branchial cavity of Callianassa subterranea, concealing 



