S^ Mr. G. R. Waterhouse on some new genera and 



so : tarsi slender ; the hindermost but little shorter than the 



tibiae. 

 Presternum rather nari'ow^ with a longitudinal groove, and not 



produced posteriorly beyond the hinder margin of the anterior 



coxae. 



In having the scutellum distinct, the eyes not crossed by the 

 lateral keel of the head, the tibiae filiform, the thorax contracted 

 behind, and the clypeus rounded in front, this genus approaches 

 Tentyria ; it has the head proportionately larger, the thorax more 

 strongly margined at the sides, the antennae longer, and the se- 

 cond joint not so distinctly shorter than the rest ; its more direct 

 affinity I believe to be with Hylithus, Thinobatis, Evaniosomus and 

 Melaphorus. Megalophrys evinces its affinity to these insects in 

 having the eye nearly round, more convex (as compared with Ten- 

 tyria), and with the lenses very large (they appear to be positively 

 larger and more distinct in the small insect, Megalophrys patago- 

 nica, than in a Tentyria of at least five or six times the bulk) : the 

 lateral lobes of the head, or folds which cover the base of the an- 

 tennae, are more produced, and separated from the clypeus by a di- 

 stinct notch in all these genera with the exception of Thinohatis. 

 None of these insects have the comparatively hard wing-cases 

 which we find in Tentyria and its approximate genera. The prin- 

 cipal distinctive characters of the South American genera above 

 alluded to, may be thus expressed : — 



I. Antennae cylindrical, the terminal joint smaller than the others. 



A. Antennae with the three basal joints equal or very nearly so ; the 



head elongated ; thorax without lateral keel. 



p . , , / Melaphorus, Guerin. 



^ \ Stenhohnay ^oWev. 



h. Eye large 2. Evaniosomus. 



B. Antennas with the second joint shorter than the first or third, and 



the third the longest ; head as broad or broader than long ; thorax 

 with a distinct lateral keel Megalophrys. 



II. Antennae incrassated at the apex, the last joint as large, or larger than 

 the penultimate. 



A. Antennae with the three basal joints nearly of equal length ; clypeus 

 truncated in front ; anterior tibiae short and distinctly dilated at 

 the apex , Thinohatis, L^schsch. 



13. Antennae with the second joint shortj the third longer than the other 

 joints; cl^^peus rounded in front ... Hylithus, 0\\qx\w. 



Megalophrys patagonica. Megaloph. picea ; antennis pedibusque 

 piceo-rufescentibus ; capite thoraceque crebre punctatis ; thorace 

 subquadrato, postice angustiore, raarginato, angulis anticis posti- 

 cisque acutis, supra subconvexo ; elytris elongato-ovatis, convexis, 

 seriatim punctatis interstitiis subseriatim punctulatis ; corpore 

 subtus punctate. — Long. corp. 4J lin. ; lat. Iflin. 



In general form this insect somewhat resembles a Tagenia, but 



