228 Recent Literature. \_a^^ 



from the enemies surrounding a terrestrial nurserj. The third and last 

 stage is represented hy the protective coloration, a device which has been 

 almost universally adopted bj nidifugous birds, owing to its greater 

 effectiveness." 



The Hoatzin is taken as the main clew to the problem. In the structure 

 of its wing "we have a i-evelation of a phase of bird-life hitherto unsus- 

 pected; inasmuch as its peculiar developmental stages, each with its 

 period of functional activity, enable us to interpret the hitherto meaning- 

 less and puzzling characters seen in the wing of the fowl and turkey, and 

 their allies. These constitute well-nigh invincible proofs of an earlier and 

 universal arboreal existence, extending back to the time of the earliest 

 known bird arch?eopteryx. Certainly the skeleton, especially the wing, 

 lends the strongest support to this view. This carries us further back 

 still, and suggests the conclusion that the reptile stock from which the 

 aves are descended was probably also arboreal." 



He explains that infant mortality could be reduced (i) by depositing 

 the eggs on the ground, or (2) curtailing the activity of the young, the 

 latter being produced hy reducing the amount of food-yolk and inducing 

 an earlier hatching period. But space will not permit us to give a synop- 

 sis of his many ingenious suggestions. — J. A. A. 



Strong on a Case of Abnormal Plumage. ^ — The case here described 

 is that of an abnormal condition in the juvenal plumage of a hybrid 

 between the Common Ring Dove (Turtur risorius) and the Red Ring 

 Dove (T. hiimilis) of China, in which the remiges, rectrices and contour 

 feathers were crossed by a subterminal band of paler color, in which the 

 barbules were imperfectly developed. "It is significant," says the author, 

 "that these abnormalities occur at uniform distances from the distal ends 

 of the feathers throughout the whole plumage, and it seems reasonable to 

 conclude that the conditions responsible for the abnormalities were con- 

 stitutional, and affected the germs of all the feathers simultaneously, 

 though in three different degrees of intensity." The abnormalities are 

 ascribed to malnutrition at the time the juvenal plumage was developing. 

 The character of the malformation is described in detail and illustrated 

 with figures. — J. A. A. 



Trowbridge on ' The Relation of Wind to Bird Migration.' - — In ' The 

 Auk' for July, 1895 (XII, pp. 259-270), Mr. Trowbridge published an inter- 

 esting paper on ' Hawk Flights in Connecticut.' The present paper con- 

 tains further observations on the migrations of hawks in southern Con- 



1 A Case of Abnormal Plumage. By R. M. Strong. Biolog. Bull., Vol. Ill, 

 No. 6, pp. 289-294, with 6 text figures. Nov. 1902. 



^ The Relation of Wind to Bird Migration. By C. C. Trowbridge. Amer. 

 Nat., Vol. XXXVI, 1902, pp. 735-753, with 3 maps. 



