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Show 1897.] MR. F. E. BEDDARD ON INTERCENTRA IN BIRDS. 47L TIN AMI. Among the Tinamous I have not seen free intercentra. ALCCE. Among the Auks intercentra are quite as general as among their near allies the Limicolae. In Uria trolle there are no less than 6 free intercentra, which lie well below the level of the centra and are but loosely attached, so that they would be very readdy detachable. There are two of these bony nodules lying side by side between the ultimate and Fig. 3. Eratercula arctica. Ventral aspect of caudal vertebra}, showing free intercentra. penultimate free caudal. In Fratercula arctica (fig. 3) there are very distinct and rather larger intercentra, which are not so loosely attached as are those of Uria • in F. cornlculata I found only five. PICO-PASSERES. In this extensive group of Birds free intercentra are infrequent and, when present, not numerous. There are, however, frequently hypocentra, which may have the form of chevron-bones. In Trlponax feddenl, for example, the last four free caudals bear double hypocentra, the free ends of which become fused in the last two, thus forming chevrons. In Hylomanes gularis there is one free intercentrum followed by two hypocentra. Dacelo gaudl-chaucll has two free intercentra and five hypocentra. I could not find intercentra in Coracias, Upupa, Megalcema, Halcyon, Merops, Rhamphastos, Collus. In Momotus lessonl there are two distinct intercentra and two hypocentra. Among Hornbills, on the other |