2O2 MEMOIRS ON THE COLEOPTERA 



of mancipata, constituting group III, I am compelled to simply 

 quote the characters given in the original description of the single 

 known species, which inhabits a geographic region far removed 

 from that of the opaca group. 



Body having the exact form of opaca, black, subopaque; head coarsely 

 punctate; prothorax coarsely and closely punctate; elytra slightly 

 broader at base than the prothorax, the humeri distinct, the margin 

 at that point slightly reflexed, transversely flat, the marginal carina 

 very nearly reaching the apex, the surface even, without costs or 

 wrinkles, having small sparse granules, each bearing a minute hair; 

 under surface of the prothorax very coarsely punctate, granulate 

 each side of the coxae, the entire mesosternum and sides of the meta- 

 sternum granular; abdomen finely, sparsely punctate, the last two 

 segments more densely; legs closely punctate. Length (9) 16.0 

 mm. Lower California (San Francisquito). [Asida planata 

 Horn] planata Horn 



This species is still represented by the unique type. 



Megasida n. gen. 



This is one of the more characteristic genera of northern Mexico, 

 being there represented by numerous species, only one of which 

 has thus far been observed to come across our boundary in western 

 Texas. The body is of large size, including some of the largest of 

 the tribe. Megasida is evidently closely related to Asidina, 

 Trichiasida and Asidopsis, but differs in its much larger mentum, 

 which is transversely parallelogramic, with rounded sides, fitting 

 closely against the obtuse sides of the buccal opening, the latter 

 moderately deep; the gular pedestal is very wide and rather short. 

 The last maxillary palpal joint is moderate in size and exactly recti- 

 triangular in the male, as in the genera mentioned, the same joint 

 in the female being still smaller and less than right angled at its 

 point of attachment. The head, eyes, labrum and antennae are 

 of the same general type as in the preceding genera. The pro- 

 sternum rapidly and almost vertically descends upon the anterior 

 margin of the mesosternum, by which the genus can always be 

 distinguished from the obsoleta group of Stethasida, to which it 

 often bears a striking resemblance as noted by Mr. Champion. 

 The legs are moderately long but rather slender, the anterior tibiae 

 very moderately everted and acute externally at apex, with a few 

 serrules along the outer edge, and the tarsi are rather long and with 



