THE GENUS KRISNA (JASSIDJE) 



By C. F. Baker 



Of the College of Agriculture, University of the Philippines, Los Banon 



FIVE PLATES 



The Orient possesses an extensive fauna of large, fine jassoid 

 insects related to Selenocephalus. These are all stout-bodied, 

 short-headed jassids and commonly with the face, or the vertex, 

 or the pronotum, or all three, coarsely sculptured, this sculpturing 

 commonly consisting of transverse rugosities or wrinkling, and 

 frequently with the clavus and the base of the corium strongly 

 punctate or rugose-punctate. The anterior border of the head 

 varies from sharp margined to very obtusely rounded between 

 the vertex and the face. 



In general, the jassids in question are distinguished by two 

 important structural characters. The antennal scrobes are large, 

 and not confined to the cheek, but involve a portion of the lateral 

 surface of the frons, and are overhung by a thick, sharp, mar- 

 gined ledge, which passes on to the frons, the carinate edge 

 curving downward on the latter, in some cases nearly to the 

 clypeus. The lateral margin of the frons thus passes upward 

 through the scrobe and cuts the supra-antennal ledge. Neither 

 previous descriptions nor drawings bring out this important 

 structural feature, and previous drawings of the face are uni- 

 formly incorrect as to this area. The ocelli are on the upper an- 

 terior border of the head or near it, near to the eyes, and often 

 visible from above. The actual superior frontal border is just 

 below the ocelli ; this suture is rarely distinct, though frequently 

 rudimentar3 r at the sides. The anterior border of the head may be 

 margined by a more or less sharp transverse carina above the 

 ocelli, and at the same time may have another similar carina just 

 below the ocelli, in which case we say that the ocelli lie in a 

 transverse furrow or sulcus. Either one or both of these carinse 

 may be absent or there may be several sharp transverse carinse. 

 Sometimes the sulcus is very narrow ; at other times, broad with 

 a few to many transverse wrinkles within. Sometimes both ca- 

 rinse are lacking, and only the transverse band of wrinkles re- 

 mains. But the wrinkles or the carinse or the sulcus, in some 

 form, are always present in the members of this group. The 



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