692 FAUNA HAWAIIENSIS 



Dolerothrips, sp. 



Like D. dtibiiis but having the prothoracic bristles as in the macropterous form of 

 D. Jlavipcs (Plate XVIII. fig. i8) and the tube slightly shorter compared to the length 

 of head. Abdominal bristles longer. 



This is a winged specimen which would appear to differ from dubtus, chiefly on 

 account of the long prothoracic bristles, and the presence of a pair of short ones at 

 anterior angles. The chaetotaxy of the prothorax is a character upon which one places 

 great reliance, otherwise it might be possible to class this form with the preceding. 

 The single winged female was taken on the Molokai Mountains at 3000 feet in June 

 1893 (Perkins, No. 185). 



We might here emphasize the difficulty of working out a genus like Dolerothrips 

 satisfactorily from dried and carded specimens, and we hope that plenty of well-preserved 

 material in alcohol will be placed at our disposal later. 



Trichothrips Haliday. 



There are two Hawaiian forms which may be tabulated as follows : — 



i. Colour chestnut-brown ; posterior ocelli remote from inner margins of eyes ; 

 tube about four-lifths the length of head and three times as long as broad at 

 base hi/icoriiis, sp. nov. 



ii. Colour black ; posterior ocelli touching inner margins of eyes ; tube less than 



two-thirds the length of head and only twice as long as broad at base nigricans, sp. nov. 



(i) Trichothrips laticornis, sp. nov. 



Plate XVIII. figs. 6—10. 



%. Length about 2-0 mm., breadth of mesothorax 0-45 mm. 



Colour chestnut-brown, coxae, forehead, sides of head, prothorax and pterothorax 

 and the apical third of each abdominal segment two to eight darker ; fore-tibiae shaded 

 with yellow, and all tarsi, and basal third and tip of third antennal joint yellowish. 



Head as wide behind eyes as long, vertex rounded, slightly raised, and bearing the 

 anterior ocellus un the apex ; cheeks slightly swollen behind the eyes and roundly 

 narrowed to base. Eyes finely faceted, occupying laterally about one-quarter the 

 length of the head ; pigment black ; post-ocular bristles long. Ocelli large and widely 

 separated, posterior pair on a line drawn through the centre of the eyes, and remote 

 from their inner margins. Mouth-cone shorter than wide at base, evenly narrowed to 

 tip, and almost reaching to the posterior margin of the prosternum ; labium pointed ; 

 labial palpi rather large. Antennae almost twice as long as the head ; joints three 

 to six broad ; joints three to five roughly and roundly obconical, sixth constricted at 

 base, seventh fusiform and eighth narrowly pyriform. Sense-cones long and acute, 

 a pair on each of the joints three to si.x. 



