1918] Weiss and Dickerson—Notes on Trioza Alacris 61 
distal tip transparent, remainder opaque. Inserted in leaf tissue 
by means of a minute extension at basal end. One side rests close 
to leaf surface and becomes flattened. Other side is convex. 
The following descriptions were made from alcoholic material. 
First Stage Nymph: Length 0.21 mm., greatest width 0.1 mm, 
Color white; shape oval, broadly rounded at both ends, slightly 
sinuate at anterior margin; broadest across middle of thorax which 
gradually narrows at posterior extremity. Abdomen narrower 
than thorax. Body segmentation somewhat indistinct, that of 
abdomen indicated. Head, thorax and abdomen subequal in 
length. Body sparsely covered with minute hairs. Eyes indicated 
by red spots on lateral posterior margins of head. Antenne length 
about one-third width of thorax, cone shaped, twice as long as 
width of base, tip slightly truncate; a minute spine arising from tip 
with a smaller one below. Legs, length, two-thirds the width of 
the thorax, gradually tapering toward tip; segmentation indistinct; 
apical end of leg bearing a sucker disc and a spine. Rostrum long, 
fine, hair-like; basal sheath extending to between bases of third 
pair of legs. 
Second Stage Nymph: Length 0.3 mm., greatest width 0.15 
mm. Color white; shape rectangular to broadly oval. Anterior 
end of body truncate, outer angles broadly rounded. Body 
gradually widening to posterior third of thorax, then gradually 
narrowing to posterior thoracic margin. Abdomen slightly nar- 
rower than thorax, posterior end rounded. Body sparsely hairy, 
segmentation indistinct. Antenne cone shaped, length one-fifth 
' width of thorax, outer extremity transversely ridged bearing two 
spines at tip. Legs similar to those of preceding stage except that 
they are proportionately larger and the sucker disc is missing. 
Tip of leg bears a pair of minute hooks. Eyes red. Basal sheath 
of rostrum extends to bases of second pair of legs. 
Third Stage Nymph: Length 0.5 mm., greatest width 0.22 mm. 
Similar to second stage in shape and color except central dorsal 
portion of thorax and posterior margins of abdominal segments 
which are tinged with brown. Lateral margin of thorax bears a 
row of minute spines. A pair of these spines on lateral margin of 
each abdominal segment. Antenne similar to those of preceding 
stage, length, one-sixth width of thorax. Eyes and legs similar to 
those of preceding stage. Basal sheath of rostrum extending to 
bases of second pair of legs. 
