502 COLEOPTERA OF NORTH AMERICA. 



Tribe I— ARRHElVODI\I. 



The genus Eupsalis, represented in our fauna by a single 

 species, difl'ers IVom Arrlienudes by the brilliant lustie of the 

 surface, and by the hind i)art of the head being- less prominent ; 

 in view of the magnitude of the variations in the l l , which we 

 have mentioned below, we have great doubt of the generic value 

 of these characters; nevertheless, our opinion can only be testeil 

 by a careful study of foreign species, which would interrupt the 

 progress of the present memoir, and is, moreover, not essential 

 for the elucidation of our own fauna. 



The distribution of Eupsalis, even as thus limited, is remark- 

 able ; one species in Atlantic North America, one species in 

 Guinea, and one in Madagascar, and ])erliaps one in Brazil. It 

 is worthy of remark in this connection, that the genus Amorpho- 

 cephalus, the only Brenthide found in Europe, is also represented 

 in Australia.* 



The development of the head of the male, and the size in both 

 sexes (*7.2-n mm.), vary in au unusual degree in this insect. 



Tribe II.— BREIVTHIIVI. 



Two species of Brenthus collected by Mr. Xiintus, at Cape San 

 Lucas, Lower California, which are closely allied to Mexican 

 species, have been fully described by Dr. Horn ;^ one West Indian 

 species, B. anchorago, is found in Southern Florida. We ob- 

 serve in the males also great variation in the form of the head in 

 different individuals, although the beak, though shorter, is as 

 slender in the % as in the 9, and the mandibles are equally 

 small, but different in form ; the distance from the eyes to the 

 insertion of the antennae is proportionally longer in the larger 

 males. 



The head is deeply excavated beneath, just in front of the 

 neck, in B. peninmlaris, while it is only slightly so in B. 

 lucanus. In B. mexica-niis there is a short but deep groove in 

 the same position. The front femora alone are toothed in B. 

 mexicanus dkW^ /wca??Ms, while they are all toothed in j^enimularis 



* Lacordaire, Gen. Cul., vii. 423. 

 t Trans. Amer. Ent. Soc, iv. 128. 



