310 PTILOTA : INTERNAL ANATOMY. 



Diirckheim, and some others, on the contrary, regard the 

 articulated tarsi as the organs of touch ; Kirby and Spence 

 considering them also as organs of active touch; whilst the 

 same authors, together with Knoch, Lehmann, Cuvier, and 

 Burmeister, regard the palpi as the organs of touch, these 

 parts being, without intermission, applied to every surface, 

 and being terminated by a minute transparent membrane, 

 which is supposed to be the precise seat of this sense ; al- 

 though Strauss-Durckheim, who carefully examined it, con- 

 sidered it as the organ of a distinct double kind of sense, 

 partaking both of touch and taste. In some bees which I 

 am at present experimenting upon, and which thrive upon 

 moistened white sugar, I notice that the maxillary palpi are 

 applied to the surface of the sugar all the time that the 

 insect continues to feed. 



B. The Digestive System. 



After the food has been taken into the mouth, and been 

 submitted to the action of the trophi, it passes into the 

 pharynx, or entrance to the stomach. The digestive organs 

 are opened at each end, extending from the mouth to the 

 anus : sometimes they are straight, and at others bent or 

 twisted together ; and, as in the higher animals, they are 

 short in the predaceous species, but elongated in those which 

 feed upon plants j sometimes they are of an equal diameter 

 throughout, but at other times variously constricted. Where 

 the number of these constrictions is the greatest, the digestive 

 tube consists of 1st, the pharynx; 2nd, the esophagus, or 

 gullet ; 3rd, the craw, or jabot ; 4th, the gizzard, or ventri- 

 culus ; 5th, the stomach, or duodenum ; and 6th, the in- 

 testines, including the intestinum tenue, or small gut, the 

 oecum, or blind gut, and the rectum, or vent gut. In addi- 

 tion to this variously-divided digestive tube, there is a 



