Mr. J. S. Baly on the Phytophaga. 281 



Fam. Megalopidae. 



Genus Mastostethus, Lac. 

 Mastostethus lavatus. (Plate XIII. fig. 6.) 



31. elongatus, parallelus, nitidus, supra subnitidus, pallide rufo-piceus, pilis 

 brevibus sparse vestitus ; antennis pedibusque nigro-piceis ; femoribus 

 flavis, dorso nigro-lineatis ; abdominis segmentorum margine, thoracis 

 angulis, epistouiatis margine apicali oreque (mandibulis piceis exceptis), 

 flavis ; elytris fortiter crebre punctatis, fere rugosis, pallide fuscis, utro- 

 que (basi excepta) flavo-lirubato. — Long. 8f, lat. If lin. 



Hob. Oaxaca, Mexico. 



Narrow, elongate, parallel, pale rufo-piceous. Face triangular ; jaws 

 elongate, acute ; epistome separated from the face by a deep transverse 

 groove, from the middle of which a short perpendicular impression runs 

 upwards on the latter ; surface of face sparingly clothed with fine hairs, 

 closely punctured between the eyes ; a narrow longitudinal space in 

 the middle smooth, inipunctate ; vertex remotely punctured ; antennae 

 moderately robust, nearly half the length of the body. Thorax nearly 

 twice as broad at the base as long, sides nearly straight, narrowed 

 from the base to the apex, all the angles prominent; upper surface 

 convex from side to side, bordered at the base and apex by a transverse 

 groove ; surface remotely punctured, anterior and posterior angles each 

 marked with a yellow patch, which extends some distance along the 

 anterior border in the one case, and along the posterior in the other. 

 Scutellum trigonate, its apex obtuse. Elytra parallel, deeply and closely 

 punctured, almost rugose towards the apex, clothed with very short 

 indistinct suberect hairs. Posterior thighs shorter than the abdomen, 

 slightly incrassate, unarmed beneath. 



Mastostethus Dohrnii. (Plate XIII. fig. 5.) 

 M. elongatus, parallelus, nitidus, dorso subopacus, niger, pilis brevibus 

 subdense vestitus; tibiis nigro-piceis; metapectore antice, abdomine 

 (segmento anali excepto), thoracis lateribus elytrisque pallide flavis ; 

 his fortiter punctatis, utroque vitta suturali antice abbreviata vittaque 

 submarginali a basi fere ad apicem extensa nigris ; femoribus posticis 

 subtus spina brevi armatis. — Long. 3|, lat. 2 lin. 

 Hob. Oaxaca, Mexico. 



Elongate, parallel. Head deeply but distantly punctured, rugose- 

 punctate on the inner margin of the eyes ; face subtrigonate, shorter 

 than in the foregoing species; jaws subelongate; epistome separated 

 from the face by a deep groove ; mouth fulvous ; antennae incrassate, 

 rather longer than the head and thorax. Thorax rather broader at the 

 base than long, sides nearly straight, narrowed from base to apex, above 

 subcylindrical, obsoletely grooved transversely at the base and also on 

 either side in front; surface smooth, glabrous, very remotely punc- 

 tured, the lateral border pale yellow. Scutellum trigonate, its apex 



