482 EXTERNAL ANATOMY OF INSECTS. 



distinct segment, is narrower than the nose, and the 

 upper-lip than the nostril-piece, forming as it were a 

 triple gradation from the front to the mouth. Again, in 

 others the part in question is received into a sinus of the 

 nose. This is the case with the dragon-flies (Libellulina), 

 in which this sinus is very wide ; in the burying-beetle 

 (Necrophorus) % in some species of which it is deep but 

 narrow ; and in a species of Tenebrio from New Holland, 

 which perhaps would make a subgenus. If you examine 

 with a common glass any of the larger rove-beetles (Sta- 

 phylinidce), you will find that the nose itself seems lost in 

 the nostril-piece, both together forming a very narrow 

 line across the head above the labrum, without any ap- 

 parent distinction between them; but if you have recourse 

 to a higher magnifier, you will find this divided into an 

 upper and lower part, the former of the hard substance 

 of the rest of the head, and the latter membranous. I 

 once was of opinion that the prominent transversely fur- 

 rowed part, so conspicuous in the face of Tettigonia F. b , 

 was the front: but upon considering the situation of this, 

 chiefly below the eyes and antennas, and comparing it 

 with the analogous piece in Fulgora laternaria and other 

 insects of the Homopterous section of the Hemiptera, I 

 incline to think that it represents the nose, and that the 

 longitudinal ridge below it is the nostril -piece c . In the 

 Heteropterous section it is merely the vertical termina- 

 tion of their narrow nose. In other insects again, this 

 part approaches in some measure to the common idea of 

 nostrils ; there being two, either one on each side the 

 nose, or two approximated ones. If you catch the first 

 humble-bee that you see busy upon a flower, you will 

 A Plate VI. Fig. 10. g'. ■> Ibid. Fig. 7. a. c Ibid. g'. 



