232 MR. F. E, BEDDARD ON DISSURA EPISCOPUS. [Feb. 4, 
contrary to what we 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 MS. notes left by the late Prof. Garrod, with a view to a 
forthcoming work upon the Anatomy of Birds, upon which Iam 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. Disswra episcopus, is precisely in the same condition. 
This bird is often spoken of as Oiconia episcopus; but it seems to 
me that the anatomical peculiarity referred to justifies its generic 
Syrinx of Dissura episcopus. 
separation—just as Prof. Garrod thought of the species of Xeno- 
rhynchus which showed the same absence of so characteristic a 
Ciconiine muscle. 
The discovery of this note reminded me that 1 had preserved at 
the time of its death the syrinx of a specimen of Disswra episcopus. 
On 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 Disswra, 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 Abdimia (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 my opinion, an additional 
reason for placing this species of Stork in a genus distinct from 
