38 Mr. H. W. Bates on 



According to Lacordaire, the Longicorns are divisible 

 into three tribes ; the Lepturides, formerly considered by 

 most authors as a fourth tribe, being sunk to the rank of 

 a subordinate group under the Ceramhycides. Having 

 traced the successive modifications of the forms allied to 

 Lepturides, in the order given by Lacordaire, I have 

 recognized the justice of this arrangement, and the error 

 of the opinion expressed in the introduction to the 

 Lamiides of the Amazons, on the same subject. The 

 Prionides are distinguished from the two other tribes by 

 the pronotum being distinct from the flanks of the pro- 

 thorax, and by the anterior coxae lying in transversely- 

 elongated sockets. In common with the Ceramhycides, 

 they differ from the Lamiides, by the palpi never termi- 

 nating in points, and the anterior tibiee being simple 

 instead of grooved on their inner sides. 



The number of Prionides obtained by me from the 

 Amazons is only twenty- six ; a small proportion of the 

 whole number found in Tropical America, namely 166. 

 A great many, however, described from other quarters, 

 will probably be found to be varieties or opposite sexes 

 of other species ; in confirmation of which opinion I may 

 point to the seven false species of one genus only, Pyrodes, 

 which I have reduced to synonyms in the following 

 descriptions. But the equatorial plains seem to be less 

 rich in the group than the borders of the tropics, or the 

 mountainous regions. The species are mostly nocturnal 

 in their habits, and of great rarity. When found 

 in situ, it is generally on the trunks, or under the 

 bark, of the largest forest trees. They fly abroad at 

 night, and are sometimes overtaken by a sudden storm, 

 and cast into lakes or rivers, whence the swell carries 

 them to the sandy beaches ; several of the species here 

 recorded have been found under these circumstances. 

 I have not thought it necessary to insert in the Prionides 

 the sections and "tribus^^ of Lacordaire; the genera 

 follow in the order of his classification. 



I. Prionides abekrantes. 



Genus Parandra. 



Latr. Hist. Nat. des Crust, et Ins. xi. p. 262. 



1. Para7idra gracillima, n. sp. 



P. elongata, angustata, mandibula dentibus molaribus 

 basalibus contiguis, apice tridentatis, orbitu oculorum 



