.4 Baker: Malayan Jassoidea 353 



e\ Upper margin of front a little extended beyond margin of 

 vertex and plainly visible in dorsal view at least at sides, the 

 lateral and anterior submarginal carinas of vertex usually 

 distinct, often very strong. 

 p. Pronotum very long, strongly produced and outcurved caudad, 

 largely covering the scutellum; head with eyes broader than 

 pronotum; vertex with a very strong thickened basal trans- 

 verse ridge; supra-antennal ledge callously thickened and 

 lobed over frontal margin; clypeus truncate or notched 

 apically and little or not exserted; sides of front not 

 . sinuate at scrobes; ocelli in marginal areas and visible 



from above or below Signoretiidae. 



p. Pronotum not produced caudad over the very large scutellum, 

 the hind border truncate or concave; head more or less 

 distinctly narrower than pronotum; vertex without strongly 

 thickened basal ridge; supra-antennal ledge neither strongly 

 callose nor lobed over frontal margin ; antenna? between the 

 eyes near middle of their inner margins. 

 g\ Pronotum short, broad, broadly rounded anteriorly, the 

 head but slightly narrower; vertex very broad, nearly 

 twice as broad as long; width of head greater than length 

 of head and pronotum together; ocelli situated a little 

 within anterior margin of crown, but outside the antero- 

 lateral carina of vertex, and invisible in facial view. 



Euacanthidse. 

 g*. Pronotum more or less narrowly rounded anteriorly, the 

 head very distinctly narrower, vertex always much less 

 than twice as broad as long; width of head always much 

 less than length of head and pronotum together; ocelli 

 in or very near lateral areas, and usually visible both 



in dorsal and facial views Pythamidse. 



e x . Upper margin of face not at all extended beyond margin of 

 vertex and not visible in dorsal view, or only little so just in 

 front of eyes; ocelli on anterolateral border of head or just 

 above or below it; loras very small and narrow; tegmina 

 usually without anteapical cells and venation usually indis- 

 tinct basally; antennas usually inserted distinctly above the 

 eyes in facial view, rarely on upper line of or between eyes, 



in which case the head is long-produced Nirvaniidas. 



<f. Basal suture of front usually obsolete, the basal lateral sutures 

 running to and terminating at or near the ocelli; vertex usually 

 clearly connate with the front, only in highly specialized groups 

 with a sharp edge or with transverse carinas on anterior border; 



ocelli on anterior border of head or above it Jassid*. 



'. Vertex more or less roundly curved on to face, and broadly visible 

 in facial view, the ocelli facial and between the eyes or above them ; 

 basal suture of front, when present, far anterior to base of face; 

 that portion of vertex visible from above usually very short and 

 broad Bythoscopide. 



