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 

 (7. c. vi. pp. .317, 318) given such a list, compiled from various 

 authors ; but the opportunities for observation of my 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 Jceraudreni. S [Lesson, Pavesi, Meyer]. [Probably 

 2 also.] 



gouldi. S • present, much less developed (sometimes absent) 



in $. 



Manucodia chalybeata. S [Pavesi, Meyer]. "] 



jobiensis. S . [Condition in 2 not known.] > 



• atra. S . [Condition in $ not known.] J 



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^. 



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 Rhynchcea 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 

 simple^ 



In R. capensis, as Mr. Wood-Mason has lately shown (P. Z. S. 

 1878, pp. 745-751, pi. xlvii.), the mature females only have a 

 sliglitly extrathoracic loop, the trachea of the younger females and 

 of the males being quite simple. 



' Two spefimeus showiug different degrees of developiueut of this structure 

 may be seen mounted in the Himterian Museum (Preps, llafi, D & E). 



