SENSE-HAIRS. 



17 



touch 



mem- 

 bear- 



of the 



(2) 



forated, and a special nerve-fibre runs to tbe base of the 

 hair. 



1. Hairs solid. 



(1) Hairs attached stiffly ; organs of 

 (Fig. 18, c). 



(2) Hairs attached by means of a thin 



brane, sometimes plumose; organs of 

 ing (Fig. 18, d). 



2. Hairs hollow, and either open at the end, or 

 closed by an extremely delicate membrane. 



(1) Hairs containing a continuation 

 nervous plasma ; 

 organs of smell 

 (Fig. 18, e). 

 Hairs generally 

 very short, and 

 situated in the 

 mouth or on the 

 mouth part ; or- 

 gans of taste 



(Fig- 18,/). 

 of these classes 

 is again subject to end- 

 less modifications, and 

 others will doubtless here- 

 after be discovered. The 

 sense-hairs are also often 

 more or less completely 

 sunk in the chitiuous in- 

 tegument. 



Fig. 19 shows some of 

 the tactile hairs on the proboscis of a fly (Musca), each 

 anglion and connected with a nerve {ii). 



c 



Each 



Fig. 19.— Part of the proboscis of a fly 

 (Musca); after Leydig. n. Nerve; g, 

 ganglionic s-svellings ; s, tactile haTs or 

 rods; c, cuticle. 



seated on a g 



