Mammals (Class Mammalia)

1. Body covered with hair
2. Mammary glands present

3.Internal fertilization
4. Placenta present

5. Complete four-      chambered heart

Two Germ layer
1. Endoderm
2. Ectoderm

Three Germ layer
1. Endoderm
2.Mesoderm 
3. Ectoderm

•An anterior appendage, such as a leg, wing, or flipper