1.Epidermal derivative
:
A. Scales in Reptiles and birds.
B. Horns: the hollow horn in cattle ( ox ,goat and
sheep)
C. Claws, Nail & Hoof: it found in amniotes
(reptilian ,birds &mammals) ,
D. Feathers: there are three principal types .
E. Hair in mammals
2-Dermal derivatives:-
A. Scales of fish
B. The external skeleton of Turtle
Antler
Placoid scales
Scutes of carapace
Scutes of plastron
