10 Psyche [February 



the labrum and help to form the tube beyond the pharynx through 

 which the setae pass. The labium is short, wide, and consists of 

 three parts, a broad basal portion (mentum?), a second smaller 

 part bearing the palpi (palpifer?), and a minute distal portion 

 bearing two minute bodies (paraglossae?). The pharynx is small, 

 well developed, and situated below the clypeus, to which it is 

 attached by lateral arms; the epipharynx and hypopharynx are 

 indistinguishable. The base of the maxillary seta is short, the 

 tip flat and acute, without barbs, and evidently only used for 

 piercing. The mandibular setae are slightly spatulate at the tips, 

 and show no traces of groove under a 1-9 inch objective. 



The paired setse we consider as mandibular, homologus to 

 those of Rhyncota, the part of the rim of the head-capsule to 

 which they were articulated having grown inwards to form the 

 mandibular pillars (h). The unpaired seta arises from the left 

 maxilla, and is part therof. The sub-triangular plates forming 

 the maxillse may be the palpifers, the other parts being reduced 

 or lost. This interpretation was confirmed on another species of 

 Tubulifera, but two species of Terebrantia differed, and showed 

 an arrangement of mouth organs agreeing with Gar man, viz: — 

 one mandibular seta on the left, and a pair of maxillary setse. 

 It is possible that this difference of mouth-parts will run through 

 these two sub-orders. 



Uzel's figure of JEolothrips Jasciata does not bear out his sug- 

 gestion that the unpaired seta is a development of the epipharynx, 

 and in the species herein figured, there is no doubt of its maxillary 

 origin. 



June, 1910. 



