CHAP, vm 



SKIN 



127 



figured in this chapter for yourself, the directions given on 

 pp. 135 — 139 are simple enough to be carried out with very 

 limited appliances. 



Fig. 38. — Vertical section of the frog's skin, highly magnified. 

 D. derm, formed of Ay! hf . hf". horizontal, and v.f. vertical fibres of connective 

 tissue, and containing b. v. blood-vessels, and fg. pigment cells. E, ejiiderm, 

 consisting of m. I. active or Malpighian layer, and h. I, horny layer of epithelial 

 cells ; c.gl. cutaneous gland in section ; cgT, in surface view ; d, duct. (After 

 Howes.) 



The Skin. — A vertical section of the skin, i.e. one taken at 

 right angles to its surface, will be seen to have the following 

 structure. 



