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Show 350 MR. W. A. FORBES ON THE TRACHEA OF [Apr. 4, simple loop, extending, in the first two species, onto the pectoral muscles, but confined in M. atra to the interclavicular area. As regards the occurrence of convoluted tracheae in the class Aves generally, it may be useful to give as complete a list as is in my power of all the hitherto recorded instances. Pavesi has already (/. c. vi. pp.317, 318) given such a list, compiled from various authors; but the opportunities for observation of m y predecessor and myself have enabled me to give, as will be seen below, a much fuller and more complete one. I have endeavoured to state exactly in what species this convolution has been observed, or has been found to be absent, as well as to state precisely the sexes of the individuals presenting the peculiarities. Unless otherwise stated, the observation has been made by Prof. Garrod or myself. A. The convolutions of the trachea are superficial, lying beneath the skin, extending often more or less onto the pectoral, or even abdominal, muscles. OSCINES. Phonygama keraudreni. 6* [Lesson, Pavesi, Meyer]. [Probably 2 also.] - - gouldi. cf : present, much less developed (sometimes absent) in $. Manucodia chalybeata. J [Pavesi, Meyer]. jobiensis. cf. [Condition in 5 not known.] > atra. cf • [Condition in $ not known.] At present it has been found in the males only of these three species, and, as already indicated, is, from Beccari's observations on M. chalybeata, probably absent altogether in the females. Fam. ANATID^E. In the males of Anseranas melanoleuca the trachea forms a very extensive double loop, extending to quite the end of the pectoral muscles. The female has simply a slight bend in the neck- Fam. SCOLOPACID^E. The females only of Rhynchaa australis [according to Gould] have a convoluted trachea, forming several folds on the pectoral muscles, and extending onto the abdomen. In the males it is simple1. In R. capensis, as Mr. Wood-Mason has lately shown (P. Z. S. 1878, pp. 745-751, pl. xlvii.), the mature females only have a slightly extrathoracic loop, the trachea of the younger females and of the males being quite simple. 1 Two specimens showing different degrees of development of this structure may be seen mounted in the Hunterian Museum (Preps. 115«, D & E). |