OR, A TREATISE ON PILE. 15 



Ductility, Elasticity and Tenacity. 



With 1,750 grains, one inch stretched Jj of an inch, elasticity entire. 

 2,000 " -jjV 



2,500 " broke. 



Button, none ; the posterior terminating in a navel resembling that of a feather, and of 

 whiskers. Shaft, bright yellow and lustrous. Cortex so thin that its presence cannot 

 always be detected. Interior a mass of white fibres with a central opening. Apices often 

 ruptured. Very difficult to crush ; when it does, separating the fibres. 



OF SCALES. These tegumontary appendages belong (among reptiles) to the Saurians 

 and Ophidians, and to fishes; but they are sometimes found upon the mammalia. 



OF THE PANGOLIN OR MANIS SCALES, AND HAIR-LIKE PROCESSES THAT GROW BETWEEN 

 AND BENEATH THEM. This animal belongs to the Order Edentata. For a general descrip- 

 tion of it see Elemens de Zoologie, p. 384. It is found in Asia and Africa, and a 

 specimen may be seen in the Academy of Natural Sciences of Philadelphia. 



The number of scales are as follows: Upon the head, 64; neck, 14; body, 122; tail, 

 160; legs, 136=496. 



There are a few hairs, or hair-like processes, issuing from between these scales, but none 

 from the scales themselves. 



Particular Description of the Scales. Form, nearly flat; slightly convex on the superior 

 and slightly concave on the inferior surface. Outline, sub-quadrilateral; the inferior 

 extremity, that connected with the skin, ovoidal at the angles ; the superior extremity 

 inclining to semi-circular. Color brown, opaque, dull. To the touch smooth, when the 

 fingers are passed longitudinally; but, when passed in an opposite direction, slightly 

 rugose. No ductility nor elasticity. 



Structure. Composed of two plates, an inferior and a superior one. 



The inferior one, (which is the smallest,) at its inferior extremity, is bounded by two 

 straight lines, which respectively commence at the inferior angle of the sides of the scale, 

 and meet at right angles. At its superior outline it is semi-circular. This superior extre- 

 mity of this inferior plate is soldered to the superior one, with an opening in the form of a 

 pouch. 



The superior plate, (which is the largest,) is divided by a slightly curved midrib, into 

 two nearly equal triangular portions. The posterior portions of each of these triangles, 

 from their inferior outlines to points opposite to the pouch, are again divided by ribs run- 

 ning nearly parallel with the midrib. The lateral edges of this plate, where they corres- 

 pond with those of the inferior one, are turned over and felled. Nearly the whole interior 

 between these plates, is filled with muscle ; and with it the midrib and ribs, which also 

 are muscular, communicate; thus enabling the animal to raise its scales, and, perhaps, 

 allowing it to communicate to them a slight lateral motion. 

 4 



