602 PROCEEDINGS OF THE NATIONAL MUSEUM. vol.46. 



with two elongate, very slender approximate processes on ventral 

 margin; styles short, pincer-like, scarcely divergent, roundly acute 

 at apex. 



Described from a macropterous pair from Acapulco, Mexico 

 (Baker). One broken female from Texas, in the United States 

 National Museum collection, may belong to this genus, but it is too 

 far gone to identify with certainty. 



Type-specimen.— Csit. No. 15981, U.wS.N.M. 



Genus MEGAMELUS Fieber. 



Delphax Authors (Part). 



Lihurnia StIl. 



Kelisia Fieber. 



Chloriona Fieber. 



Euidella Puton (Euides Fieber). 



Prokelma Osborn. 



Body rather small to medium in size, seldom large; head with eyes 

 usually narrower than prothorax, sometimes almost or quite as 

 broad; vertex usually about as long as broad, more or less variable 

 in shape, usually rather quadrate, seldom very broad, produced 

 before eyes a little (sometimes almost one-third its length before, in 

 which case it is longer than broad) ; carinae variable in distinctness 

 from very strong to rather evanescent, sometimes almost obsolete on 

 apex of head ; median carina of frons forked at or very near apex of 

 head (below in M. albolineosa sometimes) ; frons variable in shape from 

 one and a half to two and a half times as long as broad, usually nar- 

 rowed between eyes; clypeus usually tricarinate. Antennae terete, 

 seldom longer than to clypeus, often shorter, I usually distinctly 

 shorter than II. Eyes deeply emarginate beneath; ocelli near to or 

 touching lower corner of eye. 



Pronotura straight or slightly rounded on anterior margin; lateral 

 carinae variable in trend from straight and reaching hind margin to 

 more or less curved out behind eyes and not reaching margin, some- 

 times straight and becoming obsolete before hind margin, or bifurcate 

 with one branch extending to or toward hind margin and the other 

 curved outward. Scutellum tricarinate. Legs variable in length; 

 hind tibiae usually a little longer than femora; calcar from one-half 

 to fully as long as basal tarsus, more or less fohaceous, with posterior 

 margin finely or coarsely dentate. Elytra (macropterous) longer 

 than body; venation somewhat variable. Male genitalia variable; 

 female genitalia quite constant throughout the group; ovipositor 

 sheath cylindrical, extending to or nearly to tip of abdomen. 



Type of genus. — Megamelus notulus Germar. 



The generic name, Megamelus Fieber, is used here for the large 

 group of species heretofore placed in several closely related genera, 

 the largest of which was Lihurnia, or Delphax of several authors. 



