336 ASELLTD2E. 



in fully developed individuals, are longer than the whole 

 animal. The flagellum is very long, and composed of 

 a vast number of articuli, which are twice as broad as 

 long, each of which appears to consist of three still more 

 minute divisions; the inner antennae have on the second 

 joint of the peduncle a small pointed articulate scale, the 

 homotype on the large squamiform plate attached to the 

 third joint of the peduncle of the inferior antennae in the 

 macrourous Decapoda ; they are terminated by a slender 

 multiarticulate flagellum, reaching beyond the middle of 

 the long third joint of the outer pair. The fore legs (first 

 pair of gnathopoda) are somewhat more robust than the 

 following limbs, and in this pair the terminal ungues are 

 unequal in size. The parts of the mouth resemble those 

 of Jcera, except that in the mandibles we failed to detect 

 the palpiform appendage, which may have been broken 

 off. The labrum is rounded in front, with a deep 

 central incision (fig. *). 



We have restored Dr. Leach's name of Janira to this 

 genus, which Latreille, with complete disregard to the 

 rules of priority in nomenclature, had changed to Oniscoda. 

 The former name was published in the " Edinburgh 

 Encyclopaedia," vol. vii., previous to 1814, as Dr. Leach 

 himself, in his " Memoir on the Classification of the 

 Linnaean Irisecta," read at the Linnaean Society in the 

 early part of 1814, refers to his article in the " Edinburgh 

 Encyclopaedia." In 1826 Risso, finding that the name 

 Calypso, which in 1816 he had given to a genus allied to 

 Galathea, had already been used by naturalists, proposed 

 that of Janira in its stead, in the Errata to his 

 " Natural History of the Crustacea of Nice ; " Latreille, 

 however, overlooking the prior employment of the name 

 Janira by Leach, rejected that name and proposed that 

 of Oniscoda in its stead, in the *' Families Naturelles du 



