1892.] PHYTOPHAGOUS COLEOPTERA PROM MADAGASCAR. 57^ 



the latter strongly rounded at the middle, the posterior angles pro- 

 duced into an acute tooth, the surface rather convex, transversely 

 depressed at the base, entirely impunctate ; elytra strongly narrowed 

 posteriorly, fulvous, shining, impunctate, or exceedingly finely and 

 sparingly punctured, the interstices very finely wrinkled here and 

 there. 



The shape of the thorax is peculiar in this species, and the 

 posterior angles are distinctly dentate, the tooth being placed above 

 the middle line of the posterior margin, the angles themselves 

 being obliquely shaped. 



Malacosoma stkor^, n. sp. 



Piceous ; the antennae and the labrum fulvous ; thorax finely 

 punctured ; elytra more closely punctate, the punctures arranged iu 

 closely approached rows. 



Length 2-2| lines. 



Head impunctate, the frontal tubercles transversely oblique, the 

 clypeus strongly triangularly raised ; labrum pale fulvous ; palpi 

 slender, piceous ; antennae extending to half the length of the 

 elytra, pale fulvous, the joints very slender, the third and fourth 

 equal ; thorax subquadrate, about one half broader than long, the 

 sides nearly straight or slightly angulate before the middle ( $ ?), 

 the anterior angles distinct, furnished with a single hair, the surface 

 distinctly but not very closely punctured, piceous ; elytra with a 

 very slight depression below the base, closely and scarcely more 

 strongly punctured than the thorax, the punctures arranged in 

 closely approached semi-regular rows ; legs more or less fulvous ; 

 tibiae mucronate, the first joint of the posterior tarsi as long as the 

 three following joints together ; prosternum narrowly raised. 



The two specimens before me show some differences which are 

 probably sexual : in one the thorax is less transverse, with nearly 

 straight lateral margins, and the elytra have a slight purplish gloss 

 and are more irregularly punctured ; in the other specimen the 

 thorax is broader and the sides are distinctly subangulate before the 

 middle, the elytra have no metallic gloss and are more regularly 

 and less closely punctured in rows; both specimens, however, 

 apparently represent the same species ; the last abdominal segment 

 in both is simple. 



Malacosoma aterrimum, n. sp. 



Entirely black ; the thorax but slightly broader than long, im- 

 punctate ; elytra entirely impunctate. 



Length 2 lines. 



Head impunctate, black, the frontal tubercles distinct, transverse ; 

 palpi slender, the terminal joint acutely pointed ; the antennae ex- 

 tending to half the length of the elytra, black, the third joint slightly 

 longer than the second ; thorax subquadrate, about one half broader 

 than long, the sides very slightly rounded, the anterior angles 

 rather prominent, the surface entirely impunctate; elytra without 

 basal depression, rather opaque, impunctate ; tibiae armed with a 

 small spine, the first joint of the posterior tarsi as long as the three 



39* 



