78 TROGLODYTIDA. 
Prof. Baird, and lastly to a separate genus, Uropsila. This bird has a resemblance to 
Henicorhina in the proportions of its wings and tail, as well as its general coloration ; 
but instead of the open nostril of the members of that genus, the nasal opening is 
overhung by amembrane just as in Thryothorus. As it also has a compressed lengthened 
bill and short tail, it may be conveniently placed next to Microcerculus. 
The single species U. leucogastra is only known as an inhabitant of Southern Mexico. 
1. Uropsila leucogastra. 
Troglodytes leucogastra, Gould, P. Z. 8. 1836, p. 89°. 
Uropsila leucogastra, Scl. & Salv. Nomencl. Av. Neotr. pp. 7, 155°. 
Cyphorhinus pusillus, Scl. P. Z. 8. 1859, p. 372°. 
Heterorhina pusilla, Baird, Rev. Am. B.i. p. 119°. 
Murino-brunnea, loris et superciliis posticis albis; secundariis extus et cauda nigro obsolete transfasciatis ; 
regione auriculari albo variegata; subtus alba lateraliter cinerascenti tincta, hypochondriis, ventre imo et 
crisso pallide brunneis ; rostri maxilla plumbea, mandibula albida ; pedibus pallide corylinis. Long. tota 
3:5, ale 1°75, caude 1:1, tarsi 0-75, rostri a rictu 0-7. (Descr. exempl. ex Mexico. Mus. P. L. Sclater.) 
Hab. Mxxico, Tamaulipas (fide Gould), Playa Vicente (Boucard *). 
Of this small species but little is known. Mr. Gould’s description of a bird from 
Tamaulipas was long unrecognized or misapplied to the Mexican race of Thryothorus 
bewicki; and it was not until 1873 that its right title was restored to it?, Mr. Sclater having 
in the meantime redescribed the species in 1859 under the name of Cyphorhinus pusillus °. 
When describing C. pusillus Mr. Sclater had four specimens before him, all from Playa 
Vicente, on the eastern side of the mountains of Oaxaca. One of these seems to have 
come afterwards into the possession of the Smithsonion Institution*. Besides these we 
have a single specimen said to be from Mexico, but without exact locality. A sixth is 
Mr. Gould’s type, the fate of which is not known. These, so far as we are aware, are 
all the specimens that have been obtained up to the present time. 
HENICORHINA. 
Heterorhina, Baird, Rev. Am. B. i. p. 115 (1864) (nec Westwood, 1845, Coleop.). (‘Type Scytalopus 
prostheleucus, Scl., = Cyphorhinus leucostictus, Cab.) 
Henicorhina, Sclater & Salvin, P. Z. S. 1868, p. 170, vice Heterorhina, Baird. 
Prof. Baird first separated this small genus of Wrens from Cyphorhinus, with which its 
species had been perhaps more frequently associated than with any other; but the name 
chosen by him having been unfortunately previously used, Henicorhina was substituted 
for itin 1868. The open nostril lying at the anterior extremity of the nasal fossa, 
without any trace of an operculum, removes the genus at once from Cyphorhinus and 
also from Microcerculus and Thryothorus, and places it close to Thryophilus, in which 
genus the form of the nostril is quite similar. The very short tail, hardly exceeding 
