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to their insertion into the prehensile portion. Their pale fibres are 

 rendered evident by a dark vascular net work which is placed un- 

 derneath them. Through the centre of the erectile portion runs a 

 tube, CFig. 5, p.p.) which is attached behind to the style, and in front 

 is continuous witii a similar structure already described in the pre- 

 hensile portion. It is soft, whitish, and homogeneous, of uniform 

 size throughout, and remarkably extensible. When the tongue is 

 quiet in the mouth, the tube lies folded on the style ; when ad- 

 vanced, it is drawn off and elongated. It follows all the motions 

 of the organ, gliding with it alternately oflf and on the style, 

 which is rounded and smooth for the purpose ; but it cannot, as 

 some have supposed, take any part in causing the propulsion or 

 retraction of the tongue. A highly vascular structure exists be- 

 tween this tube and the encircling mucous membrane. (Fig. .3, 4, 

 5, n.n.) It extends from the root of the style to the very end of the 

 tongue, surrounding the tube equally on all sides. Its vessels, which 

 are rendered visible even to the naked eye by their dark blood, 

 appear, when examined with a magnifying glass, like a beautiful 

 trellis-work, the brunches crossing and anastomosing with each 

 other to incalculable minuteness. A coloured spot, which resem- 

 bles a mere stain, exiiibits through a glass a congeries of vessels. 

 This vascular appearance has been described by the anatomists of 

 the French Academy in the following words : La membrane eslait 

 " convert de taches tout du long comme si elle avoit este imbue en 

 " dedans d'un sang noirastre, extravase et inegalement amasse en 

 " plusieurs endroits." In another passage : " La Langue estoit 

 " semee de quantite de vaisseaux apparens a cause du sang qui y 

 <' estoit en grand abondance, ainsi que dans tout le reste du corps." 

 But the circumstance is noticed by them only to excite our astonish- 

 ment, " que Aristote ait dit que la chameleon n'a du sang q'autour 



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