TWO NEW THYSANOPTERA FROM PORTO RICO 69 



median ocellus. Antennae nearly 1 .6 times as long as head, moderately 

 slender ; segment 1 nearly as broad at base as long ; 2 slenderer than I , 

 two-thirds as broad as long ; 3 clavate, narrower than 2, twice as long 

 as wide ; 4-6 nearly similar in form to 3, successively decreasing in 

 length and breadth ; 7 elongate, slender, about two and one-half times 

 as long as broad and two-thirds as wide as 3 ; 8 subcorneal, slightly nar- 

 rowed at base, two-thirds as long as 7 ; sense cones short and weak. 



Prothorax very slightly shorter than head and (inclusive of coxae) twice 

 as wide at base as at apex and 0. 7 as long as wide ; lateral outline con- 

 cave ; surface smooth ; median dorsal line distinctly chitinized ; all usual 

 bristles present, the anterior marginals greatly reduced ; anterior angulars 

 £md midlaterals pointed, one-third as long as postoculars ; posterior angu- 

 lar and coxal longest, fully equal to postoculars, capitate ; posterior mar- 

 ginals shorter, pointed. Pterothorax about as wide as base of prothorax, 

 sides nearly straight, converging posteriorly. Legs stout, of moderate 

 length ; fore femur equal in length to head, 1 .6 times as long as broad ; 

 fore tibia stout, scarcely as long as width of femur, with a stout, promi- 

 nent tooth on inner side of apex ; fore tarsus with a long, strong, curved 

 tooth about three-fifths as long as tarsus. Wings long, slender, weak, 

 colorless, without double subapical fringe. 



Abdomen slender, slightly wider than pterothorax. Tube about 0.6 

 as long as head, basal fourth slightly swollen and twice as wide as the 

 somewhat constricted apex ; terminal bristles brown, one and one-half 

 times as long as tube ; all other abdominal bristles pale. 



Measurements of holotype (female) : Length 1 .6 mm. ; head, length 

 0.228 mm., width 0.188 mm. ; prothorax, length 0.216 mm., width at 

 apex 0.150 mm., at base 0.292 mm.; pterothorax, width 0.312 mm.; 

 abdomen, width 0.336 mm. ; tube, length 0. 1 38 mm., width at base 

 0.064 mm., at apex 0.032 mm. Antennal segments : 1 , 36[J. ; 2, 46j« ; 

 3, 56/<; 4, 51/i; 5, 49/i; 6, 44/(; 7, 45/1 ; 8, 30/i ; total length of 

 antenna, 0.36 mm. ; width at segment 3, 0.028 mm. 



Male. — Smaller and slenderer than female (length about 1 .3 mm.) ; 

 otherwise nearly similar. 



Measurements of allotype (male): Length 1.3 mm.; head, length 

 0. 1 98 mm., width 0. 1 6 1 mm. ; prothorax, length 0. 1 80 mm., width at 

 apex 0. 1 1 8 mm., at base 0.246 mm. ; pterothorax, width 0.240 mm. ; 

 abdomen, width 0.240 mm. ; tube, length 0. 1 I 4 mm., width at base 

 0.053 mm., at apex 0.027 mm. Antennal segments: 1, 33/'.; 2, 42//; 



