HLATE IX. 
MALLARD. 
Backs of the same birds as on opposite page. 
The gradual passage by coloui', assimilation :iud moulc of tlie inuuatuce Drake to tlie adult bird, completed iu five luoijtlos. 
.3,3. August. 4,5,6,7. September. 8, 9,iO. October, 11. NoT.embeE ast. 
