NO. 1310. NORTH AMERICAN THYSANOPTERA— HINDS. 151 



appear to divide the joint into short, cylindrical segments. On the 

 fourth joint the rings are minutely setate. Numerous large sette are 

 also present on all joints, most numerous on fourth. Legs stout; hind 

 femur about as long as tibia; tarsus one-jointed, terminating in claw- 

 like fork; l)ladder-like expansion of adults apparently wanting. 

 Abdomen composed of ten segments, marked dorsally with four longi- 

 tudinal rows of seta? and a row on each side. All of these setaj appear 

 to be somewhat enlarged and rounded distally, except one pair on 

 dorsum of last segment. On tentli segment these setfe are quite long, 

 being from two to four times longer than the others. 



Larva^ i<eeond stage.— h^VLgih about 1 mm.; width of thorax about 

 0.22 mm.; shape about as in stage one. Color of body deep orange 

 yellow; legs and antenna? lighter; eyes reddish; antenna? four-jointed, 

 as in tirst stage; basal joint short, cylindrical, about one-half as long 

 as wide; second, subcylindrical, somewhat longer than wide; third, 

 subconical, about a third longer than wide; fourth, about as long as 

 proximal three together, fusiform, thickest about basal fourth. Joints 

 three and four plainly ringed, the rings of fourth joint quite distinct 

 and minutely setate, as in first stage. Large sette are also present 

 about as in stage one. Femur of hind legs about as long as tibia; tar- 

 sus one-jointed, somewhat forked distally, and bearing a membranous 

 expansion. 



JS^yinph or pupa, young 7^?/7/y>/i.— Resembles the full-grown larva in 

 shape; in color it is much lighter, being light yellow, with legs, 

 antennte, and wing-pads still lighter. Eyes reddish. 



In the antenn;v, legs, and wing-pads the nymph skin appears some- 

 what as a sheath to these parts of the forming adult. The antennai 

 are three or four jointed, apparently, thick and clumsy. The basal 

 joint is large, swollen, slightly longer than wide; the second is about 

 twice as long as wide and somewhat constricted in middle. Third 

 joint is about a third longer than second, gradually tapering distally 

 to an obtuse end. When the nymph stage is first entered the antenna 

 project cephalad in normal position. In six or eight hours, however, 

 they are laid back over the head and prothorax. In the hind legs, 

 femur and tibia of about equal length; tarsus indistinctly one-jointed, 

 very short, and rounded distally. Wing-pads short, scarcely reaching 

 caudal end of second abdominal segment, bearing one or two seta?. 

 Abdomen as in larva, with dorsal and lateral rows of setai, which, how- 

 ever, are acute. On the dorsum of ninth segment, near caudal margin, 

 are four stubby, hook-like processes, curving cephalad, which appear 

 to be the four moditied setie of this region. 



Mature nymph.— l^^wgih about 1 mm.; width of thorax about 0.22 

 mm.; color light yellow; shape very similar to that of adult Thrips. 

 Nymph skin more or less separated from the body of the adult within, 

 particularly so in the legs, antenna?, mouth-parts, wing-pads, and 



