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Show 1882.] DR. W. BLASIUS ON BIRDS FROM CERAM. 697 extinct wingless birds from Dinornis. So, likewise, with parts of the skeleton which are connected with the sternum. The coracoid in Ocydromus, Notornis, Aptornis, and Apteryx * unites with the scapula at angles progressively detracting from the power of the muscles inserted into the humerus for tbe raising and protracting the wing. The coracoids, besides change of position, also lose in relative size, especially in their proximal or sternal breadth; consequently they require shorter grooves for articulation with the sternum ; and as the loss proceeds from the mesial angle outwards a greater space intervenes between the sternal ends of the coracoids. Tracing the flightless birds from the Kivis to the Wood-hens, this interspace progressively decreases ; tracing the volant species onward or upward, we find in some of the best flyers that the fore border of the sternum ceases to co-expand with sternal expansions of the coracoids, the articular grooves decussate, and the mid part of the fore border of the breast-bone shows a double articular groove. The clavicular arch, or " merry thought," manifests a concomitant loss of strength, becomes filamentary, resumes its typical character of parial " collar-bones," and finally disappears. But these gradations, with concomitant fall to keelless breast-bones, are related physiologically, narrowly or specially, to corresponding proportions of parts of the osseous and muscular systems, and, to similar degrees, with final loss of volant power. The food, the ovi-position, the nidification, and other habits of flightless terrestrial birds may show no corresponding samenesses. Such vital differences, with the several corresponding totalities of avian organization, disperse or rank the so-called " Ratite" birds, in a natural and philosophical system of Ornithology, into different reduced, perhaps extinct, groups or orders of the class: and the well-marked modifications of form and proportion in keelless sternums, exemplified in plate 57 of the third volume of our 'Transactions,' may help to point the way towards the group to which their several possessors may be shown by future found remains to be naturally affined. 2. On a Collection of Birds from the Isle of Ceram made by Dr. Platen in November and December 1881. By Dr. W I L H E L M BLASIUS, C.M.Z.S. [Eeceived November 13, 1882.] Dr. Platen, the traveller and naturalist, who has of late years become favourably known to the scientific world by his collections in Malacca, Borneo, and other places of the Indo-Malayan region, made in the month of November of last year a stay of nearly four weeks at Lokki, on the island of Ceram, going there from Amboina. He collected on this occasion forty-nine skins of birds, which have been transmitted to my friend Mr. A. Nehrkorn of Riddagshausen, and by him kindly given to me for identification and classification. 1 Trans. Zool. Soc. vol. ii. (1838) p. 257, p 55. fig. 2. |
