IX. Contributions to an Insect Fauna of the Amazon 
Valley (Coleoptera^ Priomdes) . By H. W. Bates, 
F.Z.S., Pres. Ent. Soc, 
[Eead 15th March, 1869.] 
The following pages contain a description of the genera 
and species of Longicorn Coleoptera, Tribe Prionicles, 
obtained by me in the region of the Amazons, and are a 
continuation of a series of papers commenced in the 
Annals and Magazine of Natural History, in July, 1861. 
Those papers completed the tribe LamiideSj leaving for 
subsequent publication the tribes Prionides and Ceramby- 
cides. My reasons for postponing the continuation of 
the work, on the completion of the first part, were the 
want of a general classification of the Longicorns founded 
on a study of the whole family, and a conviction of the 
inconvenience to science of partial classifications appli- 
cable only to a single fauna. Such a classification I was 
compelled to invent for the Lamiides group ; which, 
although it seemed to suit well the material I had before 
me, I afterwards found impossible to reconcile with the 
arrangements proposed by other writers, probably equally 
well-suited to other faunas. This was especially the case 
with the classification adopted by Mr. Pascoe for the 
Longicorns of the Malay Archipelago, and the incon- 
venience to which I have alluded was felt in this way, 
that it was impossible, with two such distinct arrange- 
ments, to institute those comparisons which all Naturalists 
find so interesting, between the faunas of these two equa- 
torial regions. The work which all Coleopterists inter- 
ested in this family have been so long expecting, the 
eighth volume of Lacordaire^s Genera has at length 
appeared, containing a new and well-considered classifi- 
cation of the family, and there is no longer need to delay 
the description of my collections. In so difficult a group 
it would be presumptuous to alter this classification, 
without a laborious study of material, as large as that 
which has been at the command of Professor Lacordaire ; 
and to do so in a partial manner would hinder rather 
than forward the progress of our knowledge of the 
group ; I shall, therefore, adopt it implicitly in the 
following descriptions, although I believe, in some 
points, it is far from natural in its arrangement. 
TRANS. ENT. SOC. 1869. — PART I. (APRIL) . 
