374 U. 8S. P. R. R, EXP. AND SURVEYS—ZOOLOGY—GENERAL REPORT. 
Sub-Family SITTINAE. 
SITTA, Linnaeus. 
Silta, Linnaeus, Syst. Nat. 1735. (Agassiz.) 
Cu.—Bill subulate, acutely pointed, compressed, about as long as the head; culmen and commissure nearly straight ; 
gonys convex and ascending ; nostrils covered by a tuft of bristles directed forward. Tarsi stout, scutellate, about equal to the 
middle toe, much shorter than the hinder, the claw of which is half the total length. Outer lateral toe much longer than 
inner, and nearly equal to the middle. Tail very short, broad, and nearly even; the feathers soft and truncate. Wings reach- 
ing nearly to the end of the tail, long and acute, the first primary one-third of (or less) the third, or longest. 
This genus differs from Sittella in having the bill entire, not notched, the tail longer, &c. 
There are several species in the United States, which may be arranged as follows : 
a. Crown black. 
ure! wihite beneath. Billi stoubiarcecec-ccecesesssse dosesceseeesconosen eseececessscerennen= os CONOLULENSTS: 
Similars Billislenders.vsc.ccsccctevsceessotcecs cece scewee sacar scrsscenesteneereeesmrcre cere tees MO eRCCULCOLUs 
Brownish rusty beneath, a black stripe through the e€ye.........sscseccsseeseceeeeeeee Canadensis. 
b. Crown not black. 
Crown light brown. Hind toe much longer than the middle one.................004-..9. pusilla. 
Crown greenish plumbeous. Hind toe about equal to the middle one...............5. pygmaed. 
Comparative measurements of species. 
Catal. Species. Locality. | Sex. | Length.| Stretch | Wing.) Tail. (Tarsus. | Middle Irts elaw, Bill Along | Specimens mea 
No. | of wings. | | toe. | alone. above. | gape. sured. 
— — | | 
1762 | Sitta carolinensis..... Carlisle, Pa.....-..| @ 0.70 | 0.86 | 0,24 0.70 0.88 | Skin. .ececesees 
dO. |ooeeeedO vcececcscreee|ceeeesdO soveeceveeslevenes BaeeBbod acccctied bacasced aces eeee| Fresh... 
1761 Q eceeee 2. 0.90 | 0.26 0.76 0.84 | Skin.... 
GO. |occcee JeveeeedO veveeeeeeee |eeseee . 02E 375 | ceveceleceeoses levveiesies ppsocdoa bpbocabal liceatoad Fresh... 
10209 | 3d | 0.69 | 0.78} 0.24) 0.76] 0.90] Skin...... 
10210 Q 0.80} 0.26 0.76 0.93 | Skin avons 
818 aasee lems 0.60 | 0.68| 0.22] 0.58] 0.64 | Skin.........0 
do. cel evceeeGO sccvscesces|sevees Al sccclscesvcce|coeveces|ooees o0| FCSN se sesccece 
2073 Q | 0.70 | 0.22 0.56 0.66 | Skin.... 
dO. |oc00ecdO ccccccecccecc|eveeesGO coveccceee-lecneee| 4.08 | 8.08 | 2.08 |. creceleccvcece|.cevceee | see eens |eaeeeues +. eees| Fresh... 
1925 | Sitta pusilla... | | 0.64| 0.20) 0.54] 0.68] Skin...... 0. 
3342 | Sitta pygmaea . .-| Upper California. ..|...... 0.62) 0.20 | 0.50 0:62 || Skins... sesenc. 
SITTA CAROLINENSIS, Gmelin. 
White-bellied Nuthatch. 
Sitta ewropaea, var. y, carolinensis, GMELIN, I, 1788, 440. 
Sitta carolinensis, Laruam, Ind. Orn. I, 1790, 262—Wison, Am. Orn. I, 1808, 40; pl.—Bon. Obs. Wils. 1825.—Is. 
List 1838.—In. Conspectus, 1850, 227.—Nurraut, Man. I, 1832, 581—Avp. Orn. Biog. I, 
1834, 299: V, 1839, 473 ; pl. 152.—In. Birds Amer. IV, 1842, 175 ; pl. 247. 
Sitta melanocephala, Vierttot, Gal. 1, 1834, 171; pl. elxxi. 
Sp. Cu.—Above ashy blue. Top of head and neck black. Under parts and sides of head toa short distance above the eye 
white. Under tail coverts and tibial feathers brown ; concealed primaries white. Bill stout. 
Length, about 6 inches ; wing, about 33. 
Hab.—Fastern North America to the high central plains. West of this replaced by S. aculeata. 
