ORDER COLEOPTERA. 



18^ 



turbed, a caustic fluid. The species are generally large, and 

 in the males of some, the thorax is more or less dilated behind, 

 and is terminated by two lobes.* 



Gbaphipterus. Lat. Anthia. Fab. 



Which had been confounded with the preceding, but which 

 differ from them by having their ligula entirely membra- 

 nous, with the exception of the central part, by having their 

 antennas compressed, and the third articulation of which is 

 much longer ; their abdomen, otherwise, is always flatted, 

 orbicular, and one of the two spines terminating the posterior 

 legs, is much larger than the other, and in the form of a 

 plate. 



The species of this sub-genus are exclusively peculiar 

 to Africa, and smaller than the preceding. 



Aptinus, Bon. Brachinus. Web. Fab., 



Have the final articulation of the external palpi a little more 

 bulky, especially that of the labial, and a tooth in the middle 

 of the emargination of the mentum. Their ligula otherwise 

 resembles that of the graphipteri, but the lateral division, or 

 paraglassi, form a small pointed projection ; but what dis- 

 tinguishes them more particularly, as well as the following 

 sub- genus, is that their abdomen, which is oval, and tole- 

 rably thick, encloses organs secreting a caustic liquor, issuing 

 with an explosion from the anus, evaporating immediately, 

 and with a penetrating odour. This liquor, when the ani- 

 mal is held between the fingers, produces a spot analogous 

 to that produced by the nitric acid, and even, if the species 



* See the second fasciculus of the natural history of the coleoptera of 

 Europe, the first volume of the species of M. Le Comte Dejean, the excel- 

 lent work of M. Schoenherr on thesynonimy of the insects, and the Zoo- 

 logical part of the voyage of M. Caillaud, where I have described and figured 

 the insects collected by him in Africa. 



