TRIBE DIASPIDINI 355 



prominent latadentes; vulva located near middle of pygidium, anus 

 between vulva and caudal margin; genacerores single, transverse curved 

 row of three or four cerores; insects insinuate themselves beneath 

 cuticle of food-plant. Egypt on Justicia longispina Newst. 



SPECIES OF POLIASPIS 



a. Pygidium with nine groups of genacerores, arranged 1-1(18-21)25-35, 

 four other groups forming cephalic arch, lateral group of each side 

 8-12, two mesal groups 1-2 cerores; brevaceratubae numerous; me- 

 dian pair of lobes minute, scarcely perceptible; apparently without 

 plates. Australia on Exocarpus, Santalum, Leptospermum, Ixylo- 



bium, Dillwynia. exocarpi Mask. 



aa. Pygidium with less than nine groups of genacerores. 

 b. Pygidium with eight groups of genacerores. 

 c. Pygidium with three pairs of lobes. 



d. Pygidium with second and third pairs of lobes not incised, 

 lobes similar in form, second pair smaller than median and 

 larger than third pair; median pair of lobes broad, broadly 

 rounded, distant, not divergent or confluent, entire; plates 

 apparently wanting; genacerores in eight groups, arranged 

 10-10(10-12)12-12, three other groups in cephalic transverse 

 arch, mesal group of about 10 and lateral groups of about 4 

 cerores; brevaceratubae numerous. Japan on Pinus, Abies. __ 



pini Mask. 



dd. Pygidium with second and third pairs of lobes incised, 

 lobelets subequal, all minute, blunt, triangular, second pair 

 of lobes represented by three lobelets, cephalic lobelet prob- 

 ably latadentis; median pair of lobes long, projecting, long- 

 er than broad, blunt, subtriangular, mesal and lateral 

 notches, distant, not divergent, not confluent; plates long 

 and slender, arranged 0, 0, 1, 1; genacerores in eight groups, 

 arranged 3-5(9-14)20-25, other groups in transverse row, 

 mesal group of 2-4, each lateral group of 7-8. West Australia 



on leguminous plant intermedia Fuller. 



cc. Pygidium with less than tLree pairs of lobes, 

 d. Pygidium with two pairs of lobes. 



e. Pygidium with median pair of lobes confluent at proximal 

 end. 



f. Pygidium with second pair of lobes incised, rounded, 

 margins entire, mesal lobelet larger than lateral; me- 

 dian pair of lobes confluent, at proximal end, large, 

 slightly divergent, finely and widely serrate or entire; 

 plates slender, arranged 0, 1, 1, 8-10, caudal plates 

 longer and more slender than cephalic, those of each 

 lateris arranged l-l-l-5to7, caudal group short and 

 broad at proximal end; genacerores arranged in eight 

 groups, 2-4(10-13)21-25, other three groups in trans- 

 verse row, each group 2-4; mesospiracerores about 12, 

 metaspiracerores 4-6; altaceratubae seven on each side; 



