288 PHYTOPHAGA. 



antennse and in the less elevated base of the elytra. As I have many specimens before 

 me which all resemble each other, and the locality is also a different one, I have thought 

 it best to separate the insect from P. basalis. 



9. Plectrotetra guatemalensis. 



S . Fulvous ; third and fourth joints of the antennse equal ; elytra bluish green, finely geminate punetate- 

 striate, the interstices flat. 



2 . Elytra more strongly punctured, the third and fourth interstices longitudinally costate. 



Length 2 lines.. 



Head and thorax impunctate, the latter transverse, of usual shape, the anterior angles slightly produced, the 

 basal groove deep ; antennas rather robust and of nearly the length of the body in the male, the third 

 and fourth joints equal, entire antennse fulvous ; elytra with four double rows of fine punctures extending 

 to the apex, the interstices rather broader than the space occupied by each double row of punctures, flat ; 

 intermediate tibiae with a distinct spine. 



$ . Elytra with several longitudinal costse, at the sides of which two are more highly raised and distinct than 

 the others, surface more strongly punctured ; terminal joints of the antennse piceous. 



Hab. Guatemala, Zapote (Champion). 



P. guatemalensis cannot be mistaken for any of the preceding species on account of 

 the four double rows of punctures of the elytra. P. clarki, which has the same kind 

 of punctuation, is much larger, and has quite different antennse, the latter in the present 

 species being much less robust, and the third and fourth joints equal. 



10. Plectrotetra sallsei. 



tf. Fulvous; antennse robust, third joint much longer than fourth; elytra violaceous blue, rather strongly 

 punctate- striate, the punctures forming single rows, interstices slightly costate. 



$ . Antennae with the third and fourth joints equal, the rest piceous ; elytra deeply punctate-striate, the 

 interstices regularly and strongly costate. 



Length 2| lines. 



Hab. Mexico, Tuxtla (Salle). 



In the robust antennse, of which the third joint is much longer than the fourth, the 

 present species agrees with P. clarki and P. proxima, from both of which it is distin- 

 guished, as well as from others described here, by the punctuation of the elytra, which is 

 arranged in single, regular, and closely approached rows, the interspaces being slightly 

 costate near the suture and the apex; the base of the elytra is also slightly 

 raised. 



Female specimens from the same locality which I refer to this species have the 

 interstices regularly costate, and the punctures between them here and there doubled, 

 which is especially noticeable at the sides, where the costse separate a little more than 

 at the disk. The strongly raised and regularly placed costse will separate the female of 

 this species from that of P. basalis, the latter of which has the base of the elytra much 

 more strongly raised. 



