Oryzoborus crassirostris crassirostris (Gmelin). —F. P. and A. P. Penard (l. c., 1910, ii, p. 387) describe habits, nest, and eggs fully, with similar remarks in regard to variations in shape and coloration of eggs, both types sometimes being found in the same nest.
Sporophila bouvronides (Lesson). F. P. and A. P. Penard (l. c., 1910, ii, p. 392, sub nom. S. ocellata) compare nest to that of S. minuta, and eggs with those of S. castaneiventris, but say that the eggs of this species average a little longer and also a little grayer, with remarks in regard to the two types of eggs.
In another chapter the author gives much interesting information regarding the habits of Tinamous. By an ingenious experiment he is led to the discovery that birds of the genus Tinamus sleep at night in trees, while those of the genus Crypturus always pass the night upon the ground. He accordingly correlates this difference in habits to the character of the back of the tarsus, which in Tinamus is rough, and in Crypturus quite smooth. He goes on to say (l. c., p. 255):
“These two distinctions have been recognized for many years—Tinamus for more than one hundred and thirty, and Crypturus for a hundred and six years, and during all this time ornithologists have accepted this character without thought or question.”
I may say that the roosting habits of Tinamous are well known to hunters in Surinam, and according to Mr. Beebe himself they were not unknown to his Akawai hunter, Nupee, in whose statements, however, Mr. Beebe seemed disposed to place less confidence than in his own experiment, notwithstanding the fact that in either case conclusive evidence could only be sought in actual observation in the field.
Nearly one hundred years ago Charles Waterton (Wanderings in South America, 1825, p. 286) called attention to these habits and suggested that the state of the tarsus might have some bearing upon them. These are his words:
“There is something remarkable in the great Tinamou, which I suspect has hitherto escaped notice. It invariably roosts in trees; but the feet are so very small in proportion to the body of this bulky bird, that they can be of no use to it in grasping the branch; and, moreover, the hind toe is so short, that it does not touch the ground when the bird is walking. The back part of the leg, just below the knee, is quite flat, and somewhat concave. On it are strong pointed scales, which are very rough, and catch your finger as you move it along from the knee to the toe. Now, by means of these scales, and the particular flatness of that part of the leg, the bird is enabled to sleep in safety upon the branch of a tree.”
In regard to the “small Tinamou,” Waterton (Ibid., p. 287) says, “The foot of this bird is very small in proportion, but the back part of the leg bears no resemblance to that of the larger Tinamou; hence one might conclude that it sleeps on the ground.”
Here then, we have at least one naturalist to whom “the casual, nominal affair between Hermann and Illiger versus Tinamus and Crypturus” was not all.
But Waterton was not the only writer who has mentioned these things. Schomburgk, (l. c., p. 749) under the name Trachypelmus subcristatus [= Tinamus major (Gmel.)], speaks of the relation of the rough tarsus to the bird’s habit of roosting in trees, but under Crypturus variegatus (Wagler) (Ibid., p. 748) says that he does not know whether that species also passes the night in trees. More recently F. P. and A. P. Penard, under the names Tinamus subcristatus (l. c. 1908, i, p. 318) and Crypturus variegatus (Ibid., p. 322) definitely state the bearing of the construction of the tarsi in these two genera upon the dissimilarity in roosting habits.