42 Mr. H. W. Bates on the Longicorn Culeoptera 



vious writers. Although a faunistic work, it comprehended here 

 and there the results of the examination of genera found in 

 other parts of the world. The treatise of M. Thomson consists 

 of an application of Leconte's classification to the Longicornes 

 in general. Both these essays, however, leave much to be de- 

 sired, for reasons to be mentioned presently. The only other 

 works which contain considerable modifications of the system of 

 Latreille are Mulsant's ' Coleopteres de France (Longicornes)/ 

 1839, and Blanchard's ' Histoire des Insectes,' 1845. The 

 former, although containing an excellent analysis of the species 

 and genera found in France, added little that could be applied 

 to the family generally. The latter proposed a number of sub- 

 tribes, but with insufficient and inapplicable characters, and 

 without any review of the genera comprehended under them. 



Leconte divided each of the tribes of Latreille into a number 

 of subordinate groups, characterized after a searching examina- 

 tion of the whole external structure of the insects. It is doubt- 

 ful, however, whether his groups can be all maintained : the 

 classification is open to much objection, and, I think, will require 

 considerable emendation before being applied generally. The 

 important discovery of a very constant character for the tribe 

 Lamiaires, viz. the existence of an oblique groove on the inner 

 side of the fore tibiae, is due to Zimmerman, who first called 

 attention to it. The existence of a smaller similar groove sur- 

 mounted by a tubercle on the outer side of the middle tibise, in 

 most of the divisions of the same tribe, was not mentioned. 

 The form of the anterior acetabula, or sockets of the fore 

 haunches, is employed too rigorously : it is a constant character 

 in some groups of Lamiaires, being a good guide, for instance, 

 in distinguishing the Colobothese from the true Saperditse, with 

 which they had been confounded by all previous authors ; but it 

 separates Acanthoderes and its allies too widely from Oreodera, 

 Dryoctenes, and similar genera, with which they are in all other 

 characters closely connected. In fact, some of these genera are 

 extremely variable in this character. The form of the anterior 

 acetabula depends upon how far the suture which runs from 

 their external rim to the line which separates the pronotum from 

 the pectus is opened or closed. This suture seems to be that 

 which separates the episternum from the epimera, and, according 

 to the shape or manner of action of the fore haunches, it is 

 either quite closed, more or less gaping near the rim of the 

 socket, partly closed but not gaping at its commencement, or 

 widely opened along its whole length. The shape of the aceta- 

 bula in the Prionidse was noticed long before the date of Le- 

 conte's treatise, viz. by the Marquis Maximilian Spinola, in a 

 paper published in 1842. In this tribe, where the breast is very 



