404 



Hitchcock's anatomy 



able to fly through perfectly dark and irregular narrow pas- 

 sages, and avoid all obstructions simply by the delicate sensi- 

 bility of its membranous wings. 



742. Touch in Birds— The only portions of the skin in 

 Birds, on which tactile papillae exist, are found on the under 

 surface of the foot, and the web of the web-footed birds. The 

 bill of the Duck seems also to subserve the sense of touch, 

 upon the inside of which the skin is soft, and has many 

 branches of the fifth pair of nerves distributed to it. 



743. Touch of Reptiles. — The sense of touch seems to 

 exist in Reptiles, though the prominent use of the skin is to 

 afford a protection to the body. It is quite probable that the 

 acuteness of this sense in these animals is no greater than 

 what is derived to the Horse through the hoof, or to a man 

 through a stick or rod in the hand. 



744. Touch of F i s h e & —Fishes probably have a still 

 more imperfect sense of touch than Reptiles. It is pos- 

 sible that the lips may give an imperfect idea of the form 

 of external objects ; but the surface of the body, covered 

 as it is with scales and a thick mucous secretion, can be 

 of no service in this sense. A few fishes have hair-like 

 appendages about the head, which put them in a condition 

 to be acquainted with the presence of external objects, though 

 they are not by any means organs of active touch. 



745. Touch of Articulates— This sense is well devel- 

 oped in all the Articulates, and shows itself especially in the 

 antennae, the palpi, and feet ; and though these organs have 

 a tough, hair-like consistence, yet they are efficient instru- 



Where in the bat? 742. Where are papillae found in birds? What answers the pur- 

 pose of papillae in the duck? 743. What is said of the sense of touch in reptiles? 744. 

 Where is the sense of touch located in fishes ? 745. Describe the sense of touch in articu- 

 lates. 



