ALBINISM. 



15 



present as conjectural. Wliatever be the real explanation, the 

 facts slio\vn by the specimens in this bay are very curious, and 

 worthy of careful consideration. 



The next case on the east side of the middle of the hall Group iUus- 

 contains a series of specimens illustrating albinism, a condition ^j^'^f^i 

 in which the pigment, or colouring matter, usually present in 



Fig. 1. — The Leaf-Buttekflt (Callima inachis) in Flight and at Rest. 



the skin, and giving the characteristic hue, is aljsent. Indi- 

 viduals in this condition occur among many animals of various 

 kinds, and are called " albinos." In some of the specimens shown 

 in the case the albinism is complete, but in many it is partial, 

 the absence of colouring matter being limited to portions of 

 the surface only. 



