ALBINISM — MELANISM. 
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the tissues constituting the external covering of the body, and 
giving them their characteristic hue, is absent. Individuals 
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, 
Fig. 1. — Leaf-Buttkrfly (Callima inacliU) in Flight and at Rest. 
the absence of colouring matter being limited to portions of 
the surface only. 
The adjacent case shows examples of the opposite condition. Group ilius- 
called melanism, depending upon an excess of dark-coloured $JgJ^g„j 
pigment in the skin and its appendages the hair, feathers, etc., 
i)eyond what is normally met with in the species. This is by 
no means so freipient as albinism. A black Leopard in the 
