PLATTEHYJSrCHUS.— EHTNCHOCTCLrS. 7 



Supra olivescenti-olivaeeus ; alis et cauda fuscis umbrino limbatis ; vertioe medio castaneo utiinque nigro margi- 

 nato ; Ions, superciliis, ciliis ipsis, tectricibus auricularibus et corpore subtus flavidis ; stria postoculari et 

 altera infra oculos nigris ; hypoehondriis sordide olivaceis : rostri maxiUa nigra, mandibula sordide alba, 

 apice albida; pedibus paUide coryUnis. Long, tota 3-4, al^ 2-15, caudffi 0-8, rostri a rictu 0-5, tarsi 0-5. 

 (Deser. maris ex Santa Pe, Panama. Mus. nostr.) 



2 marl similis. 



Eab. Costa Eica, Valza (Carmiol^); Panama, Bugaba^, Volcan de Chiriqui, Santa 

 Fe 5 (Arce), Lion Hill {M'Leannan i ^ 3)._GuiAifA 7. 



This, the smallest of the three species of Platyrhymhus found within our region, 

 appears to be not uncommon in the State of Panama and in Costa Eica, as specimens 

 have been included in most of the large collections made in those districts. We find, 

 however, no accounts of its habits, though doubtless, like its congeners, it frequents 

 the underwood of the denser forests. Mr. H. Whitely met with the same species at 

 Bartica Grove in British Guiana ^ ; it occurs also at Albina in Surinam, It has not 

 yet been noticed, elsewhere in South America, though we expect it to be found in 

 suitable places in the country intervening between Guiana and Panama. 



The only southern species at all closely resembling P. superciliaris is P. coronatus 

 of the Upper Amazons valley. But the latter is a larger, darker bird, with a less 

 clearly-defined yellow under surface. 



EHYNCHOCYCLUS. 



Cydorhynchus, Sundevall, K. Vet. Ak. Handl. 1835, p. 83 (nee Kaup, 1829) (type Platyrhynchus 



olivaceus). 

 Rhynchocyclus, Cab. & Heine, Mus. Hein. ii. p. 56 (1859) ; Sol. Cat. Birds Brit. Mus. xiv. p. 165. 



Twelve species are included in Rhynchocyclus as a whole, all of them belonging to 

 the Neotropical Eegion, the range of the genus extending from Southern Mexico to 

 South Brazil. All the members are forest birds, as are the species of Platyrhynchus. 



This genus seems to us to be quite out of place in Mr. Sclater's arrangement, where 

 it stands in the " Elaineinse " next Myiozetetes. 



The bill of B. brevirostris is constructed almost exactly like that of Platyrhynchus, 

 the nostrils are similarly shaped and placed in the same position, and the rictal bristles 

 are equally developed. The tarsi are comparatively shorter and the tail much longer. 

 The secondaries are longer in proportion to the primaries, and the members of the 

 genus generally of larger size, and of olivaceous rather than brown tints. 



Rhynchocyclus is divisible into four sections, only two of which occur in our region. 

 In one of these sections [E. brevirostris and its allies) the male is distinguished by the 

 peculiar structure of the outer web of the outermost quill, the barbs of which are 

 slightly recurved and pointed so as to form a stiflF pectinated edge, much as in the 

 genera Stelgidopteryx, Oxyrhamphus, &c. 



The section containing R. sulphurescens and its allies has not this peculiarity. 



