164 



PSrCHE. 



[February — March iSSg. 



curved, scraping hairs. A few taste- 

 cups were also noticed scattered in a 

 row along the outer edge of the galea 

 of the female. 



Taste-cups on the maxillae of Bo- 

 reics califor7iicus. — No taste-cups were 

 observetl on the labium of Boreus^ 

 which is very different in shape from 

 that of Panorpa^ unless four or five pits 

 protected by two or three spines and sit- 

 uated at the base of the palpi are such. 

 On the ])asal region of the galea of the 

 maxillae, however, there is a series of 

 taste-pits, the basal one the largest. No 

 liair arises from the centre, and the pits 

 are protected in front and on the outside 

 by unusually short and stout peg-like 

 defensive setae. 



The structure of both the labium and 

 maxillae of the mecaptera is ver\- inter- 

 esting, but space forbids our entering 

 into farther details. 



Olfactory rods on the palpi of Pan- 

 orpa and Boreus. — At the qwA of the 

 second or distal joint of the labial palpi 

 of Panorpa is the usual pale area, bear- 

 ing about iS small short rods, which are 

 probably olfactory- ; these are as usual 

 roughl}' ai-ranged in two series, and b\- 

 groups. I1ie last joint of the maxillar\- 

 palpi bears olfactory rods of the size and 

 number of those in the labial palpi. 

 The end of the distal joint of the very 

 short labial palpi o{ Boreus, is provided 

 with about ten small olfactory rods which 

 are slightly larger than those of the max- 

 illary palpi. 



The rather acute end of the maxillarN' 

 palpi terminates in a pale clear space 

 through which can be dimly seen the 



nerves leading to the seven or eight 

 olfactory rods, which themselves are a 

 little smaller than those of the labial 

 palpi. Also at the distal end of the 

 second joint are four sensory pits. 



Phe olfactory pits of the antetniae 

 of Pauorpa and Bo reus. — In the ter- 

 minal antennal joint of the female of 

 Pa nor pa there are to be seen on one 

 side about 3=; olfactoi'y pits scattered ir- 

 regularly among the setae. In both 

 sexes of Boreus, there are to be seen on 

 one side of the last joint about eight 

 olfactorv pits, none at the end ; on the 

 penultimate joint there are on one side 

 five pits, three in a row on one side, 

 two on the other ; the third and fourth 

 joints from the end have two on the side 

 next to the observer, the hfth and sixth 

 one each. 



Of course the exact function of these 

 antennal pits is hvpothetical until deter- 

 mined by repeated experiment : but 

 provisionallv they mav be regarded as 

 olfactory in their natin^e. 



In conclusion we mav sav that Iw the 

 use of the creosote and oil of turpentine 

 mixture, the sense-organs can be easih' 

 examined superficiallv, and it is very 

 fascinating work. It should, however, 

 when possible, be supplemented by the 

 preparation and examination of sections, 

 after the most rigorous and exact histo- 

 logical methods, so as to reveal the ner^•es 

 and ganglion cells of special sense. 



The specimens of Boreus were kindly 

 given me by Dr. A. Agassiz, Director 

 of the Museum of Comparative Zoology, 

 Cambridge, Mass. 



