185 



in Ihe search for insects, and which it may settle and keep steady 

 when so retracted. 



The moveable portion of the tongue consists of two parts, which 

 are distinct from each other both in their structure and functions. 

 One of them I propose to name prehensile, the other erectile. 



The first, or prehensile portion, is anterior (Fig-. 2, 3, 4, 7, E.) 

 It is somewhat cyhndrical, about one inch and a quarter in length, 

 and an inch in circumference. Its bulk undergoes no change 

 during the elongation or retraction of the tongue, in consequence of 

 its being surrounded by a dense fibrous sheath, which prevents 

 any such alteration. Its anterior extremity is hollowed into a pouch 

 lined with mucous membrane, (Fig. 3, 4, 5, F) which is rugose, 

 and smeared with a viscid adhesive matter for entangling the insects 

 it strikes against. During the projection of the tongue the lips of 

 this pouch are everted so as to expand considerably its surface. Its 

 posterior extremity is smaller than the anterior, and continuous with 

 the erectile portion. The anterior half of its superior surface is 

 occupied by an oblong glandular body (G), from which perliaps is 

 secreted the glutinous coating of its extremity. The openings of 

 this gland are on its lower surface, next the pouch, on which it rests. 

 (Fig. 5, m) On the posterior half of this surface the ramifications 

 of large blood-vessels are observable. Along its sides, posteriorly, 

 the insertions of the hyo-glossi muscle present themselves. Its infe- 

 rior surface is smooth and rounded. A tube (Fig. 5, p. p.) about 

 the thickness of a small crow's-quill runs through its centre. This 

 tube is prolonged into it from the erectile portion, and serves as a 

 resting place for the style of the os hyoides, which it surrounds like 

 a sheath, when the tongue is drawn into the mouth. It is encircled 

 by an annular muscle, (Fig. 5, o. o.) the fibres of which are very 

 numerous and strong, and have but a loose connection with the 



VOL. XV. G G 



