158 Miscellaneous. 



The differences in the eggs of Humming Birds are not very ob- 

 servable ; they are invariably two in number, white and oblong, with 

 one supposed exception, — namely, that of a species inhabiting the 

 Upper Amazon, which, according to Mr. Edwards, lays a spotted egg. 

 But the differences of structure in the nests sufficiently corroborate 

 the generic di^"isions into which these birds have been separated by 

 modern ornithologists. 



Most of the nests exhibited were from the collection of Mr. Reeves 

 of Rio, who presented them to Mr. Gould in the most liberal man- 

 ner, with a A-iew to assisting him in the completion of his monograph 

 of this family. — Pt'oc. Zool. Soc. July 26, 1853. 



On a Marsupial Frog (Notodelphys ovifera) frorn Venezuela. 

 By Dr. D. F. Weinland. 



Under the name of Notodelphys ovifera. Dr. Weiuland has de- 

 scribed a singular frog lately received by the Berlin Museum, the 

 female of whicii possesses large dorsal sacs for the reception of the 

 ova. These sacs open by a fissure in the skin of the back near the 

 anus ; they were full of eggs in the specimen examined by the author, 

 but had no communication with the cavity of the body. The eggs 

 were only fifteen in number, of large size, and contained embryos in 

 a forward state of development, exhibiting a broad head, very similar 

 in form to that of the parent, and already furnished with distinct 

 eyes. The body of the embryo terminated in a short tail, at the base 

 of which the hinder feet were visible. The anterior feet were also 

 developed. The embryo had no sucking disc attached to the throat. 

 The external branchise consisted of a pair of large membranous bill- 

 shaped organs attached to the branchial arches by long vascular fila- 

 ments, two to each bill. 



In its general structure theanimal approaches the Tree-frogs (/7y/«), 

 and it appears not improbable that the Hyla niarsupiata of Dumeril 

 and Bibron, which also possesses a dorsal sac, may belong to the same 

 genus. — Midler s Archiv, 1854, p. 449. 



Descriptions of Two New Species of Ptilonopus. 

 By George Robert Gray, F.L.S. & F.Z.S. 



Ptilonopus chrysogaster, G. R. Gray. 



Crown purplish white, margined posteriorly with yellow ; sides of 

 the head, neck and breast greyish white, with the base of the feathers 

 of the latter yellow ; throat and cheeks pale yellow ; abdomen and 

 under tail-coverts bright yellow ; sides of the former greyish white, 

 tinged with yellow ; back bronzy green ; greater wing-coverts, ter- 

 tials and secondaries bluish green, narrowly margined with yellow ; 

 quills dull black, with the outer web tinged with green ; tail bronzy 

 green, with a very broad apical margin of white, each feather mar- 

 gined with yellow. — Total length, 8f inches. 



Hab. ? Probably from Otaheite. 



This species is closely allied to the Pf. purpuratus {Columha jn/r- 

 purata, Gmel., C. oopa, Wagl., Pt.furcafus, Peale), but it is easily 

 distinguished by the yellow on the abdomen, &c. 



