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Show 124 DR. R. W. SHUFELDT ON THE [Feb. 3, is constrained to say that, " Thus in the large series of types which I have determined to compare together, it has seemed fit to m e to take a very small territory; yet that territory contains parts that have undergone the greatest amount of metamorphosis of any in the whole body of a high and noble vertebrate, and moreover being, in the bird, the skeletal framework of the whole upper face, these parts are, as it were, an index of the amount of specialization undergone by any particular type-the ruling determining structures that lead to all, and really demand all, the changes that take place in the rest of the organism. This is especially explained for the benefit of those w h o will accuse me, and have already accused Professor Huxley, of taking a narrow view of the Bird-types-touching with the point of a needle some little tract, but unacquainted with and not able to appreciate the Bird as a whole." After long thought and, as stated above, after many dissections of Woodpeckers of various genera, the writer is led to believe in regard to this question that-(1) The P I C I are peculiar in regard to certain osseous structures of the cranium, but inasmuch as all the rest of their organization exhibits a high order of specialization, nearly equalling some of the highest among birds, these few characters must not be considered as being the representatives of the corresponding parts, in structure and arrangement, as found among some Lizards. W e have abundant evidence of the Reptilian origin of birds without damaging this evidence by straining such points as these. (2) That inasmuch as the vomer in all adult birds, even in the Ostrich-types, is single and median, the " medio-palatine " of Parker must be considered the vomer of the Pici. And when other small, median ossifications are found along in the line of the vomer, when the latter is present, they are simply adventitious ossicles occurring in the soft, membranous medio-septa of these vertebrates; such structures are occasionally seen in certain Hawks and Owls. (3) That the processes designated as the vomers of the Pici by Professor Parker are merely apophysial outgrowths of the mesial borders of the palatines, and as the palatines are paired bones in A V E S , we cannot conceive of such a structure in them as a " medio-palatine." (4) That they are not desmognathous means nothing in a saurian sense, for even among the so-called Desmognathae, Flanus is a non-desmognathous bird; and that the "maxillo-palatines" are but little developed in the Pici, applies also with almost equal truth to the Trochili, where we find them much reduced. (5) That the fact that the basipterygoid processes are arrested would not especially entitle them to be called a saurognathous group. W e see the same in some Accipitres, and they are functional in the Owls and other highly organized birds. (6) That we do not believe that the pterygoid of a Woodpecker in any way especially answers to that bone in a Snake or a Lizard, any more than does the pterygoid of any other highly specialized bird. And further, that some of the peculiarities of the Pici m a y be due to the fact that these birds have long used their bills to strike |