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Show 1882.] ANATOMY OF THE TODIES. 449 special resemblance ; but, as already pointed out, though the arrangement is similar, it is not identical, whilst, on the other hand, that characterizing the Todies could easily be produced by a slight modification of that found in some of the other groups of Anomalo-gonatae. In the face, then, of the many important differences that exist in all parts of the structure of the two forms, and in the absence of any special features common to them, I cannot agree to the proposition that the Todies are more closely related to the Motmots than to any other group. In the possession of caeca and in the conformation of their pectoral tract the Todies agree with all Garrod's " Passeriformes," with one of the families of which indeed, the Galbulidce, one of the most acute ornithologists that has ever lived, the late Mr. Blyth, associated them as a special group, " Angulirostres" K On the other hand, in possessing a well-developed tuft to the oil-gland, the Todies differ altogether from the Passeriform series of Anomalogonatae. Detailed comparison of the structure of tbe Todies with that of the other families of this great group is unnecessary, none of them possessing features indicating such affinities to the former as to render probable any particular genetic connexion of the two. As Dr. Murie has already remarked, "Todus is inconsistent in several respects,"2 a truth made more obvious by the facts above recorded. In the possession of caca combined with the tuft to the oil-gland, Todus presents an exception to Garrod's definition of his group Anomalogonatae3, though it agrees with all of them in the absence of both the ambiens and accessory femoro-caudal muscles. Nevertheless it is certain, from its characters generally, that Todus is an Anomalogonatous bird, though its isolation from any other of the families of that group seems to me to preclude its insertion in the Piciformes, Passeriformes, or Cypseliformes of Garrod4. It is impossible, I think, to say that Todus is more clearly related to any of the Piciformes than it is to the Passeriformes; and to include it the definitions of either of those groups would have to be altered. I propose, therefore, to create a group of equivalent value to those just named, which may be called " Todiformes," and of which Todus is the sole living representative. . Next, as to the meaning of these facts. I think few ornithologists who have carefully considered the question can doubt that the " Anomalogonatae " of Garrod are a natural group of birds5, i. e. one descended from a common ancestor. On this view this ancestor must have possessed the sum of the characters-supposing, unless there is reason for the contrary, that the latter have not been redeveloped, and excluding those that may reasonably be supposed to 1 Charlesworth's Mag. Nat. Hist. ii. 1838, p. 361. 2 P. Z. S. 1872, p. 678. 8 P. Z. S. 1874, p. 118; Coll. Papers, p. 216. 4 L. c. p. 222. , ,, , ., , ,, T, .. 6 It is nearly certain that the Cuculidae and Musophagidae, as also the Peit-lacidae, are in no way related to the other so-called Picanae. |