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Show 232 MR. E. E. BEDDARD ON DISSURA EPISCOPUS. [Feb. 4, contrary to what w e find in typical Storks (cf. fig. 3, p. 234), the membrana tympaniformis is well developed and the bronchidesmus is incomplete. This Stork, however, agrees with other Storks in the absence of intrinsic syringeal muscles and in the modification of a large number of the last tracheal rings. In looking through the M S . notes left by the late Prof. Garrod, with a view to a forthcoming work upon the Anatomy of Birds, upon which I am at present engaged, I find that the two Storks above mentioned are not the only ones in which the ambiens muscle is absent. A third species, viz. Dissura episcopus, is precisely in the same condition. This bird is often spoken of as Ciconia episcopus; but it seems to m e that the anatomical peculiarity referred to justifies its generic Fig. 1. Syrinx of Dissura episcopus. separation-just as Prof. Garrod thought of the species of Xenorhynchus which showed the same absence of so characteristic a Ciconiine muscle. The discovery of this note reminded m e that 1 had preserved at the time of its death the syrinx of a specimen of Dissura episcopus. O n examining this syrinx, I found that it presented quite the same anomaly of structure (from the Ciconiine point of view) as does Abdimia. It is very interesting to find here also-correlated with the deficient ambiens-a syrinx that approaches the Ardeine in its characters. In Dissura, however, the bronchidesmus is complete as in the typical Storks; but the membrana tympaniformis, as may be seen from the drawing exhibited (see fig. 1), is well developed, quite as well as in Abdi77iia (see fig. 2, p. 233). I need not trouble the Society with a detailed description of the syrinx of the bird, since the accurate drawing shows all its features of interest. It may be generally pointed out that the terminal rings of the trachea are Stork-like as in Abdimia, and that there are no intrinsic muscles : but that the membrana tympaniformis is Ardeine, with a well-developed pessulus. This is, in m y opinion, an additional reason for placing this species of Stork in a genus distinct from |