60 SMITHSONIAN MISCELLANEOUS COLLECTIONS [voL. 48 
instability and unsatisfactory nature of generic type determinations 
by elimination. 
The genus Orthorhyncus was instituted by Lacépéde? for the 
“ Oiseaux mouches,” undoubtedly of Buffon, a group of twenty-four 
species, to one of which the name of course must be applied; so that 
Orthorhyncus stands on equal basis with the other names of Lacépéde 
proposed in the same place, which have been subsequently accepted 
without question. The type of Orthorhyncus was fixed as Trochilus 
cristatus Linneus by Gray in 1840;? and happily enough the same 
species also becomes the type if this be determined by elimination. 
The species of this group should therefore stand as follows: 
Orthorhyncus cristatus cristatus (Linnzus). 
Orthorhyncus cristatus emigrans Lawrence. 
Orthorhyncus ornatus Gould. 
Orthorhyncus exilis (Gmelin). 
DROMZAUS Vieillot 
This name, spelled as above, does not occur in Vieillot’s “ Analyse,” 
and so far as we are aware was never used by this author. He does, 
however, in the main part of this work propose Dromiceius for the 
emus, type Casuarius novaechollandie LatHam ;° and in the supple- 
mentary list where he gives the derivations of his generic names, 
he inserts instead of Dromiceius the term Dromaius* which Ran- 
zani later emended to Dromeus? Since Dromiceius can scarcely be 
considered a typographical error for Dromaius, it follows that the 
former, standing first in the book, becomes the proper name for the 
genus. 
The species are: 
Dromiceius novehollandie (Latham). 
Dromiceius ater (Vieillot). 
Dromiceius irroratus (Bartlett). 
Dromiceius patricius (De Vis) (fossil). 
Dromiceius gracilipes (De Vis) (fossil). 
Dromiceius queenslandie (De Vis) (fossil). 
HYDRORNIS Milne-Edwards 
The fossil genus Hydrornis Milne-Edwards® is preoccupied by 
Hydrornis Blyth, used for a member of the Pittidee (Paludicola 
1Tabl. Ois., 1799, Pp. 9. 
2 List Gen. Birds, 1840, p. 14. 
3 Analyse, 1816, p. 54. 
4 Analyse, 1816, p. 70. 
5 El. di. Zool., w1, pt. 1, 1821, p. 98. 
6 Rech. Oiseaux Foss. France, 1, 1867, p. 362, Tb. 57, fig. 18-22. 
