MO SYLVIA ATRICAPILLA. 



the base, compressed towards the end, and sharp ; the upper 

 mandible with the dorsal outline nearly straight and sloping, 

 until near the tip, which is a little declinate and narrow, the 

 ridge rather distinct, the sides convex, the edges sharp and 

 slightly overlapping, with a faint notch ; the lower mandible 

 with the angle of moderate lengih, rather narrow and rounded, 

 the dorsal line ascending, and very slightly convex, the sides 

 sloping outwards and convex, the edges sharp and direct ; the 

 gape-line nearly straight. Both mandibles are concave inter- 

 nally, with a slightly prominent median line. The palate is 

 flat, the posterior aperture of the nares oblongo-linear, papillate 

 on the edges. The aperture of the glottis also papillate, and 

 with numerous papilloe behind. The tongue is emarginate and 

 serrulate at the base, with a large conical papilla at each angle, 

 narrow, horny, grooved above, thin -edged, terminated by two 

 lacerated acute points ; its length three-twelfths and three- 

 fourths. The oesophagus is two inches and a quarter long, its 

 average diameter two-twelfths and a half The stomach is 

 elliptical, nine-twelfths long when distended, its lateral muscles 

 large, the lower very thin, its cuticular lining thin and rugous. 

 The intestine is seven inches long, its diameter at the upper 

 part two and a half twelfths, at the cceca one and a half ; the 

 cojca a twelfth and a half long, and one inch from the extremity. 

 Plate XIII. Fig. 8. 



The head is oblong, and of moderate size ; the whole form 

 slender ; the aperture of the eyes two-twelfths in diameter ; 

 that of the ear two and three-fourths ; the nostrils elliptical, 

 and a twelfth and a half long. The feet are of ordinary length, 

 slender ; the tarsus compressed, acute behind, anteriorly with 

 eight distinct scutella ; the toes slender, compressed ; the hind- 

 toe broad and flat at the base, with eight scutella above, the 

 second with ten, the third with eleven, the fourth with ten 

 scutella. The claws are of moderate length, arched, extremely 

 compressed, laterally grooved, very acute. 



The plumage is soft and blended ; the feathers oblong, with 

 loose filaments, and a very slender plumule. Those at the 

 base of the bill bristle-tipped ; the bristle-feathers scarcely 

 distinguishable. The wings are of moderate length, broad. 



