330 Zoological Society : — 



7. Myiobius crypterythrus. 



Fuliginoso-fuscus; uropygio brunnescentiore ; pilei plumis interne 

 rubris ; loris albis ; alls nigricantibus alba bifasciatis, tectri' 

 cum majorum et minorum necnon secundariorum marginibus ex- 

 ternis fulvescenti- albis : Cauda fusca, marginibus pallidioribus : 

 subtus albus lateraliter cinerascens, pectore nigricanti-cinereo 

 Jlammulato, tectricibus alarum inferioribus albis : rostra et pe- 

 dibus nigris, mandibula inferiore carnea. 

 Long, tota 5*0, alse 2*5, caudae 2-3, tarsi 0-7. 

 Hab. In republ. Equator, reg. occidentalibus. 

 Mus. P. L. S. 



This Myiobius is nearly allied to M. ncevius (Bodd.) (PI. Enl. 574, 

 fig. 3) of Brazil, and of the same form and distribution of colours ; 

 but it is easily distinguishable by its larger size, sooty colouring 

 above, and red crest. It appears to be common on the western side 

 of Ecuador, examples having been procured by Mr. Fraser at Palla- 

 tanga, Babahoyo, and Esmeraldas. 



8. Myiobius cryptoxanthus. 



Fuliginosus, uropygio magis olivaceo ; pilei plumis interne Jiavis : 

 loris albis : alis nigris albo bifasciatis, tectricum majorum et 

 minorum apicibus necnon secundariorum marginibus externis sor- 

 dide albis : cauda fusco-nigricante, rectricum marginibus ex- 

 ternis dilutioribus et harum ipsis apicibus anguste albis : sub- 

 tus sordide cinereus, gutture albicantiore, abdomine fiavido 

 perfuso ; rostro et pedibus nigris illius mandibula inferiore 

 carnea. 

 Long, tota 4*5, alse 2*3, caudse 2*1, tarsi 0*6. 

 Hab. In rep. Equator. 

 Mus. P. L. S. 



This species is closely allied to the preceding, but may be distin- 

 guished by its smaller size, shorter bill, yellow hidden crest, and yel- 

 lowish belly. Its discovery is also due to Mr. Eraser's researches, 

 the only examples of it I have seen having been obtained by him at 

 Gualaquiza and Zamora, in Ecuador. It is included in my list of 

 Mr. Eraser's birds collected in those localities given in our ' Pro- 

 ceedings ' for 1859*. but not named, as I was not then able to deter- 

 mine it satisfactorily. 



January 8th, 1861.— Dr. Gray, V.P., in the Chair. 

 On Typical Selection, as a means of removing the 



DIFFICULTIES ATTENDING THE DoCTRINE OF THE OrIGIN 



OF Species by Natural Selection. By E. Vansittart 



Neale, F.Z.S. 

 The great interest excited in the scientific world by the theory of 

 the origin of species proposed by Mr. Darwin, and the obscurity ne- 

 cessarily attached to many of the data employed in the arguments 



* See P. Z. S. 1859, p. 458, sp. 59*. 



