34 Memoirs on the Coleoptera 



All but four of these genera are at present monotypic, but they 

 seem to be necessitated by very peculiar and isolated types of 

 structure. 



Testalthea n. gen. 



The type of this genus resembles Diorymerus in general characters, 

 but the body is more rhomboidal, with laterally rather prominent 

 though rounded humeri, and it differs a good deal in appearance, 

 due to the anteriorly more shouldered prothorax, with remarkably 

 punctate pronotum. The prosternum and antennae are of the 

 Diorymerus type, but the beak is more cylindrical, the mandibles 

 closely decussate and very obtuse. The genus differs, however, 

 from all others in the peculiar thick subparallel tarsi. The basal 

 abdominal segment is strongly and closely punctate, but the concave 

 median part is polished and with only a few remote smaller punc- 

 tures. The type may be thus described : 



Testalthea puncticollis n. sp. — Rhombic, very strongly convex, shining and 

 glabrous, piceous, the upper surface rufous, the posterior two-thirds of the elytra 

 black; prothorax at apex, head, beak and tarsi black, the beak nearly as long as 

 the head and prothorax, moderately thick, evenly and moderately arcuate; an- 

 tennae short, with large and elongate club, inserted slightly behind the middle, 

 a groove extending forward from the scrobes to somewhat beyond the middle; 

 punctures fine, not very dense; prothorax slightly wider than long, the converging 

 sides nearly straight, rapidly rounding anteriorly to the arcuate and tubulate 

 apex, which is less than half as wide as the base, the basal lobe deeply sinuate for 

 the scutellum; surface evenly convex, impressed at each side of the median lobe, 

 coarsely, closely punctate throughout, with a narrow entire smooth median line; 

 scutellum large, subquadrate, with rounded angles, rounded at the base, finely 

 punctulate, the median line much elevated as an obtuse ridge; elytra barely 

 longer than wide, nearly a third wider than the prothorax, triangular, with broadly 

 arcuate sides, the narrow individual apices rounded; striae very coarse, deep, 

 finely, remotely punctate along the bottom; intervals broadly convex, with very 

 fine sparse and confused punctulation; under side of the prothorax, meso- and 

 metasterna and mes-epimera very coarsely punctate, the met-episterna more 

 finely and closely, especially anteriad; metasternum with a deep smooth median 

 impression; legs strongly, densely punctate; tibiae with a very large sharp external 

 tooth near the base; fourth tarsal joint very short and thick. Length ( 9 ) 4-8 

 mm.; width 3.25 mm. Brazil (Santarem). One specimen. 



Easily recognizable by the rhomboidal outline, coloration and 

 sculpture, large and axially elevated scutellum, coarse striae and 

 rather convex intervals. 



Diorymerus Sch. 



Diorygomerus G. & H. 



The extremely numerous species, which may be estimated for 

 Brazil alone to amount to at east three hundred, adhere to a very 

 constant structural type as defined above, but there are nevertheless 

 many opportunities for the taxonomist to record them systemati- 



