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ral structure of setaceous antennae. On making a section of the an- 

 tenna, he found its interior supplied with a limpid fluid, and that it 

 possessed, in addition to a delicate central nerve, two silvery tubes or 

 tracheae, deiived from some cruciform branches in the head : " their 

 structure in every respect resembled that of other tracheaj ; " and Mr. 

 Newport imagines that many branches of these antennal tracheae com- 

 municate with the minute holes on the exterior of the antenna. 



Mr. Newport next relates the result of his experiments on living in- 

 sects ; and first on a Silpha obscura which had lost one of its antennae : 

 on his approach the insect, instead of running away, stopped and moved 

 its remaining antenna in every direction without apparent object. He 

 confined a second specimen for sixteen hours without food, and placing 

 it in a glass, attached a small piece of flesh to a wire, and brought it 

 within half an inch of the insect. The antennae moved about on either 

 side, the head was elevated and the palpi were vibrated with rapidity ; 

 the insect approached the meat and touched it several times with the 

 antennae, but suddenly withdrew them: it soon afterwards commenced 

 feeding, and the motion of the palpi then ceased. " During the ex- 

 periment it was sufficiently proved that the creature discovered its food 

 by the faculty of smell, and its immediate contact by that of touch 

 with the palpi and antennae ; " but nothing was observed tending to 

 prove that the sense of smell resides in the antennae. In the summer 

 of 1830 Mr. Newport observed many water-insects sticking to the sides 

 of an out-house that had been newly tan'ed; it occurred to him they 

 must have been attracted by the smell of the tar, as it emits an odour 

 of carburetted hydrogen gas, which gas is formed abundantly in stag- 

 nant pools, the usual resort of the species which he observed. Expe- 

 riments on fish prove that they may be attracted from a distance by 

 immersing odoriferous substances in the water which they frequent. 

 Mr. Newport kept a specimen of Hydaticus cinereus three days in a 

 cup of water, without food ; he then introduced a piece of meat on a 

 wire, passing it along the sides of the insect, and then near its anten- 

 na, when, without moving that organ, the insect began to vibrate its 

 palpi very briskly: the antennae were then touched with the meat, and 

 the insect withdrew them as if annoyed ; the insect afterwards seized 

 the meat when placed in front of it, and began to devour it : from this 

 experiment Mr. Newport again concluded that antennae were not the 

 organs of smell. The next experiment was on an individual of Lucanus 

 Cervus, which had been kept fourteen days without food : a piece of 

 wheaten bread moistened with water vvas placed about a foot from the 

 insect : it raised its head, extended its antennae, moved its palpi and 



