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Show 128 ON THE SAUROGNATHISM OF THE PICI. [Feb. $> the elbow. Seven prominent osseous papillae occur at nearly equal distances apart down the shaft of the ulna. The flat, rounded process from the postero-upper third of the shaft of index metacarpal is present. The slender last metacarpal extends below the one of index, and its free digital joint is larger than either of the other terminal phalanges. The proximal phalanx of index digit has its posterior blade almost entirely aborted. There are no claws. 31. Femur is always pneumatic, and so m a y be the tibio-tarsus in some species. In the former the trochanter major does not rise above the summit of the shaft; the excavation on the head is very shallow. Shaft nearly straight; condyles rather small; popliteal fossa and rotular channe very shallow. Pici possess patellae. Cnemial crest of tibio-tarsus elevated above summit of bone, with pro- and ecto-cnemial ridges nearly or quite aborted. Condyles of this bone very distinct, and intercondyloid valley very deep. Bony bridgelet confines tendons in front. Fibula short and free, its lower spicula-like end being held well away from shaft of tibio-tarsus by the increasing height of fibular ridge on the latter bone. Hypotarsus of tarso-metatarsus both grooved and perforated for passage of tendons. An erect process occurs on the summit of this bone of the leg. Its shaft is nearly straight, and its terminal trochleae are specially modified to meet the podal requirements of the picine zygodactyle foot. Joints of pes normal, 2, 3, 4, and 5 to the first, second, third, and fourth toes respectively. Fourth toe permanently reversed, and first toe, together with its free metatarsal bone, m a y be entirely absent (Picoides). A larger sesamoid articulates with a special trochlea (intended for it) to the inner side of the fourth toe. The osseous claws usually large, and the other phalangeal joints more or less laterally compressed. The tendons of the leg sometimes ossify to a certain degree, and minute sesamoids may occur in certain tendons near the knee-joint. Brief Remarks on the probable position of the Pici in the System, and on their Ajffines. Huxley in his " Celeomorphae " comprehended only the Picidce and Iyngidce, and Parker long ago said that " the ' Celeomorphae' of Huxley form a most natural and well-defined group-a group equal, zoologically, to the Pigeons or the Parrots. Evidently this differentiation has taken place through the gradual extinction, during long secular periods, of conjugational types more generalized than those now extant." In this much the present writer agrees with the two great authorities we have just quoted. To those at all familiar with the osteology of existing birds it must be very evident that in an anatomical system, at least, the Pici hold many characters in common with the Passeres, a fact that will be evident when we come to treat of that group later on. It is m y opinion that it is to the great Passerine group that the Pici are more |