522 BULLETIN 50, UNITED STATES NATIONAL MUSEUM. 



etc.); tertials veiy slighth^ to decidedly pi'oduced. Tail two-thirds to 

 tive-sevenths as long" as wing, two and a half times or more longer 

 than tarsus, half or more hidden by upper coverts, emarginated or 

 double-rounded, the rectrices rather narrow, l)ut not pointed. Tarsus 

 less than twice as long- as exposed culmen, its scutella indistinct or 

 obsolete on outer side; middle toe, with claw, as long- as or longer than 

 tarsus; lateral toes relativeh' short, their claws not reaching beyond, 

 sometimes falling short of, base of middle claw; hallux about equal 

 in length to outer toe, its claw variable as to relative length, some- 

 times decidedly longer, sometimes shorter than the digit. 



Coloration. — Above more or less yellowish, the back usually streaked 

 with dusky; beneath yellow, or largely so. 



Range. — Tropical South America; one species in southern Mexico 

 and Guatemala and one in Jamaica, 



Although regarded by Dr. Sharpe as closely related to Sermus 

 Koch, the resemblance seems to me to be a purely superticial one, not 

 involving structural characters, which are so ditierent that the two 

 genera scarcely need comparison. The supposed structural dif- 

 ferences given on page 161>, vol. xii. of the ''Catalogue of Birds 

 contained in the British Museum,"^ 1 am unable to appreciate, the 

 tomia being in reality quite as much deflected basally in Sicalis as in 

 Stfinafi. though there is a slight difference, that of Serinus Gormn^xic- 

 ing a little farther forward. Serlnufi, however, has a well-developed 

 fringe of antrorse plumules quite concealing the nostrils, and also a 

 rictal fringe nearly hiding the deflected portion of the commissure, as 

 in Sjjiiim, Carpodacm^ and other true ''Finches;" has the bill much 

 broader in proportion to its depth, and the tail proportionally longer 

 and more deeply emarginated. In Sicalls the nostrils are fully 

 exposed, the coccothraustine nasal and rictal fringes of Sermus being 

 quite v/anting, as in other so-called •'Buntings.'' 



The resemblance in coloration between some of the species of Sicalis 

 and a species of the Old World genus Serinus (S. canarim) is, how- 

 ever, remarkable; so much so, in fact, that were it not for the differences 

 in structural details it would be very difficult to distinguish them. 



Although at one time I considered the smaller, conspicuously streaked 

 species of Sicalis as generically distinct and proposed to place them 

 in a separate genus (Serinopsis), I now l)elieve that they can not 

 be separated, certain species being quite intermediate in structural 

 characters. 



KEY TO THE SPECIES OF SICALLS. 



a. Inner webs of primaries edged with yellow; wing more than fio.OO. (Jamaica.) 



Sicalis jamaicae (p. 528.) 



'10. Inner webs of primaries edged with pale brownish gray; wing less than 65.00. 



(Southern Mexico and Guatemala. ) Sicalis chrysops ( p. 528. ) 



' 0^ Tomium deflected toward the gape -11 ■ Serim's. 



d"". Tomium straight for its whole length 42. Sycalis. 



