168 
Philippine Journal of Science 
1919 
while two others ( Epipsylla and Melapsylla appear to be limited 
to these Tropics. These five genera are included in the following 
key, a more nearly complete synopsis of the subfamily being 
available in my monograph. 
Subfamily characteristics are not numerous. The gense are 
always more or less produced into either conical or flattish, spat- 
ulate processes, vertex not cleft in front, usually more or less 
flat ; antennae always slender, either short or long. Basal tarsus 
of hind legs always with two clawlike spines at apex ; hind tibiae 
with or without basal spur. Forewings oval or rhomboidal, 
very seldom acutely pointed at apex, always with cubital petiole 
(media and cubitus with common stem). 
The most closely related subfamily appears to be Pauropsyl- 
linse, and this differs in several characteristics, chiefly the almost 
humpbacked thorax, the usually absent genal processes, usually 
visible frons, short metacoxal spurs, and several others of less 
constancy. 
Although not strictly a part of the pakeotropical fauna, Frog- 
gatt’s Australian genera of this subfamily are included in the 
following key: 
' Key to the genera. 
o'. Genal processes conical, acutely or bluntly pointed; pterostigma of 
forewing closed (occasionally wanting) ; antennas at least longer 
than width of head. 
b'. Genal cones as long as or longer than vertex, slender and acute, 
directed forward; antennae very long, usually longer than body, 
forewing with or without pterostigma Epipsylla Kuwayama. 
b 2 . Genal cones shorter than vertex, usually directed more or less down- 
ward. 
c\ Pleural suture of prothorax extending to middle of lateral extrem- 
ity of pronotum; genal cones broad and bluntly rounded, usually 
extending more or less parallel with plane of vertex; forewing3 
often maculated Arytaina Foerster. 
c'. Pleural suture of prothorax extending obliquely to posterior corner 
of lateral extremity of pronotum; genal cones usually declivous, 
more or less acutely pointed ; forewings usually clear. 
Psylla Geoffroy. 
a 2 . Genal processes flat, broad, not conical in outline; antennae seldom long, 
usually very short. « 
b 1 . Genal processes large, broad, more or less quadrate, scarcely divergent; 
antennae seldom very short, though usually moderately so. 
c*. Genal processes in same plane with vertex; flat; eyes more or 
less recessive and flattened; forewing often rhomboidal, with 
closed pterostigma or none Euphalerns Schwarz. 
c 2 . Genal processes depressed somewhat from plane of vertex; scarcely 
flat; eyes usually hemispherical; forewings not rhomboidal, with 
pterostigma Arytaina Frst, also Eucalyptolyma Froggatt. 
b 3 . Genal processes short and rather broad; antennse very short. 
