TWO PORTO RICAN THYSANOPTERA FROM SUGAR CANE 41 



Prothorax slightly more than half as long as head and (inclusive of 

 coxae) about 2.65 times as wide as long ; surface smooth, with median 

 thickening near middle ; all bristles stout, capitate, and subequal in length, 

 the posterior angulars longest and nearly equal in length to postoculcirs ; 

 coxal bristles shorter, capitate. Pterothorax not wider than prothorax ; 

 sides nearly straight, slightly converging posteriorly. Wings not narrowed 

 at middle, sparsely fringed, lightly shaded with brown, and with faint 

 median dark line ; fore wings with three or four interlocated hairs on 

 posterior margin. Fore tarsi unarmed. 



Abdomen slightly wader than pterothorax. Tube two-thirds as long 

 as head and about 2.2 times as long as basal width, which is slightly 

 more than twice the apical. Abdominal bristles pointed, brownish ; ter- 

 minal bristles 0.8 as long as tube. 



Measurements of holotype: Length 1.16 mm.; head, length 0.180 

 mm., width 0.151 mm. ; prothorax, length 0.096 mm., width (inclusive 

 of coxae) 0.254 mm. ; pterothorax, width 0.252 mm. ; abdomen, width 

 0.264 mm. ; tube, length 0. 1 20 mm., width at base 0.056 nun., at apex 

 0.027 mm. Antennal segments: I, length 27/<, width 33/^; 2, length 

 4 1 n, width 26/JL ; 3, length 47 fi, width 25 fi ; 4, length 49//, width 25// ; 

 5, 47 fi; 6, 45 fi; 7, 40//; 8, 30/«; total length of antenna 0.33 nun. 



Described from nine females taken at Rio Piedras, Porto Rico, Janu- 

 ary 20, 1 9 1 4, by Mr. Thomas H. Jones, of the Porto Rico Sugar Pro- 

 ducers' Experiment Station. Mr. Jones's notes say that the specimens 

 were "collected from leaves of shorter, smaller, stalks of sugar cane. 

 Characteristic thrips injury was noted on the leaves, especiaUy where sur- 

 faces of the same leaf had been drawn close together by an Hesperid 

 larva or from some other cause, thus forming a shelter." 



The tibial coloration, the presence of two sense cones on the outer 

 surface of the third antennal segment, the prolongation of the eyes on the 

 ventral surface of the head, and the form of the wings, are indicative of 

 a very distinct species. The last two characters are possibly of generic 

 value, though several species ordinarily placed without question in the 

 present genus have the wings only slightly more narrowed at middle. 

 The facies of the insect is that of a true Haplolhrips. 



