February— March 1SS9.] 



PSYCHE. 



163 



appears to be the end of the clypeus are 

 two narrow thickenings of the surface, 

 along which are scattered taste-cups, 

 there being about 20 on each side of the 

 median line.^ There is also a taste-cup on 

 an area corresponding to the thin, front 

 edge of the labrum, about midway be- 

 tween the most distal taste-cup, and the 

 tip of the mandible-like thickening. 



While the epiphaiynx of Panorpa 

 scarcely projects beyond the acute end 

 of the labrum, and is apparently di- 

 vided into two large lateral divisions, 

 and moreover is divided into a basal and 

 distal portion (a somewhat significant 

 fact in connection with the possibility 

 that the labrum represents a pair of ap- 

 pendages) ; in Boreus the parepipharynx 

 extends well beyond the end of the 

 labrum, and shows no signs of a division 

 into lateral or longitudinal lobes. It is a 

 somewhat crescent-shaped whitish fold, 

 tending in front of the labrum to a dis- 

 tance nearly half its width. There are 

 no taste-cups on it, but around the edge 

 a series of about 16 large taste-rods, 

 which project as far as the marginal 

 hairs situated between them. They are 

 considerably, about twice, as long as 

 those at the extremity of the epipharynx 

 of Patiorpa. 



iVU of the hairs appear to be of the 



i) It should be observed in view of the figures by 

 Dr. W. Patten, Studies on the eyes of arthropods, 

 Journ. morphology, July, iSSS, v. 3, pi. 7, p. 1-7, of the 

 labrum oi Acilius, which appears to answer to a pair 

 of limbs representing a first pair of antennae; that in 

 Boreus, besides the bilateral mandible-like thicken- 

 ings the labrum also appears to be slightly divided 

 along the middle by these two parallel ridges or thick, 

 enings, giving rise to the appearance of an obsolete 

 median suture. But this needs further examination. 



kind denominated gathering hairs, and 

 we do not appear to have the marked 

 differentiation into different kinds of 

 hairs and setae noticeable in the epipha- 

 rynx of Panorpa. They are in Boreus 

 arranged in about six curvilinear series ; 

 and are broad at the base, not triangu- 

 lar, but with parallel sides until in the 

 middle they suddenly contract into hairs. 

 They are probably neither specially tac- 

 tile or protective, but rather adapted for 

 gathering liquids and promoting their 

 flow down the throat. 



Taste-cups on the labiutti and max- 

 illae of Panorpa. — In the same species 

 {P. debills?) I have noticed taste-cups 

 on the labium in two regions ; a group 

 of five or six on the upper surface, 

 on each side at the base of the first or 

 basal joints, also a group of about a 

 dozen on each side of a region includ- 

 ing the base of the labium and end of 

 the mentum. These taste-cups are char- 

 acterized by having a short minute hair 

 arising from the centre of the cup. 

 They were observed in the male, but 

 undoubtedly occur in the other sex, as I 

 have not as yet observed any sexual dis- 

 tinctions in this group as regards the 

 distribution either of gustatory or olfac- 

 tory organs. 



In the maxillae of the same species 

 there are in both sexes a few taste-cups, 

 protected by long defensive setae on the 

 stipes near the base of the palpi ; and in 

 the male I noticed a group of five such 

 pits at the base of the lacinia, while 

 others are scattered along the outer edge, 

 near the base of the singular series of 

 marginal comb-like sets of flattened, 



