42 THE REPORT OF THE No. 36 



cc. Sides of prothorax without bristles; 



d. Interocellar bristles located on the sides of the ocellar triangle; 



e. The inner of the two prominent bristles on the anterior margin of 

 the prothorax nearly twice as long as the outer. 



Parafrankliniella Priesner. 

 ee. The outer of the two bristles the longer. 



Frankliniella Karny. 

 dd. Interocellar bristles between the posterior pair of ocelli. 



Kakothrips Williams.* 

 bb. Anterior angles of prothorax without a strong bristle; 



c. Posterior angles of prothorax with only one strong bristle on each side; 

 d. Head little broader- than long; fore wings not regularly set with 

 bristles. 



Scirtothrips Shull. 

 dd. Head one and one-half times as long as broad. Fore wings with 

 a continuous row of bristles on both wings. Pscudothrips Hinds 

 e. Antennae apparently 9 segmented. Pseudothrips. 



ee. Antennas clearly 8 segmented. Glaucothrips Karny. 



cc. Antennae clearly 8 segmented. Posterior angles of prothorax with two 

 strong bristles on each side; 

 /. The front and the eyes greatly enlarged. The 8th abdominal 

 segment without comblike teeth on the posterior margin. 



Cricothrips Trybom. 

 ff. Shape of the head normal. A comblike structure usually present 

 on the posterior margin of the 8th abdominal segment. 



Tceniothrips Serville.f 

 g. Sixth antennal segment normal. 



Tceniothrips. 

 gg. Sixth antennal segment sharply pointed. 



Rhopalandrothrips Priesner. 

 aa. Fore tibiae armed at the end with one or two teeth; 

 g. Antennae 8 segmented. 



Odontothrips Serville. 

 gg. Antennae 7 segmented. 



Sminyothrips Uzel. 



Of the genus Frankliniella erected by Karny in 1910, over forty species 

 are now recognized. Thrips intonsa Trybom was erected by Hood as the geno- 

 type, but there is a question whether it is correctly designated. Frankliniella 

 tritici Fitch, the species we are concerned with at this time, is briefly described 

 as follows: 



FEMALE: Length 1.1-1.2 mm.; width .2-. 26 mm. 



Head: three-fourths as long as broad; back of head transversely striated; ocelli subapproxi- 

 mate pale yellow, margined inwardly with reddish-orange crescents; interocellar spines long, 

 postocular spines shorter, both conspicuous; antennae, about two and a half times as long as 



*Dr. Karny separates these three genera on the presence or absence of abdominal processes 

 on the 8th segment. Inasmuch as certain reduced but recognizable processes may be found in 

 certain female species of Frankliniella this character would not appear to be so useful in differ- 

 entiation as the location of the interocellar bristles. 



fDr. Karny separates Physothrips Karny from Tceniothrips Serville by the presence or 

 absence of transverse bands on the fore wings. This character is not well stabilized; hence 

 Physothrips falls within the genus Tozniothrips. Amblythrips Bagnall and Pezothrips Karny 

 were both erected for wingless species. Information has been received that winged forms have 

 been taken, hence, the characters being the same, the two genera also fall within the genus 

 Tceniothrips. 



