LANIID.E — TUE SHRIKES. 421 



coloration of the tail, these were considered as resulting from an imperfect 

 description. Messrs. Sharpe and Dresser, however, as quoted above, show 

 that Swainson's type really belongs to L. luhtora, an Old World species. 

 We therefore find it expedient to give a new name to the variety, having no 

 reason to discredit tlie alleged locality of the specimen. 



Collurio ludovicianus, vur excubitoroides, Baird. 



WESTERN LOGGERHEAD ; WHITE-RUMPED SHRIKE. 



Zanius excubitoroides, Sw.\ixsON, F. B. A. II, 1831, 115 (Saskatchi;wau>. — (l.iMBEL, I'l'. 

 A. N. Sc. 1847, 200 (Cala.). — C.vssiN, Pr. A. N. Sc. 1857, 213. — ScL.vrER, P. Z. S. 

 1864, 173 (City of Mexico). Colli/rio exx-ubitoruidcs, Baird, Birds N. Am. 1858, 327. 

 Collurio excub. B.4IRD, Rev. Am. B. 1864, 445. — Cooper, Om. Cal. I, 1870, 13S. 

 ? Lanitts mexicatiiis, Brehm, Cab. .Jour. II, 1854, 145. — Sclatf.r, Catal. 1861, 46 

 (Mexico). Lanius ludovicianus. Max. Cab. Jour. 185S, 191 (Upper Mis.souri). — 

 Dkesser & SiiARPE, P. Z. S. 1870, 595. 



Had. Western Province of North America, as far north as Oregon ; Middle North 

 America, to the Saskatchewan, and east to Wisconsin, Michigan, and Illinois ; south to 

 Orizaha and Oaxaca, and City of Mexico ; Cape St. Lucas. 



The precise boundaries between this species and C. ludovicianus are diffi- 

 cult of definition, as the transition is almost insensible. 



The young bird is pale fulvous-ash above, everywhere with transverse 

 crescentie bars of dusky. Two Viands of mottled pale fulvous across wings, 

 on tips of middle and greater coverts. Tail tipped with ochraceous, the 

 white feathers tinged with the same. Breast and sides with obsolete bars of 

 dusky. Black band on side of head rather obsolete. 



In its extreme stage of coloration it differs from hulovicianus in paler and 

 purer color ; the ash of back lighter ; the under parts brilliant white, not 

 decidedly plumbeous on the sides as in the other, and without so great a 

 tendency to the usual obsolete waved lines (noticed distinctly only in winter 

 or immature birds) ; the axillars bluisli-white, not plumbeous. The white 

 of wings and tail is more extended ; tlie hoary of forehead and whitish of 

 scapulars more distinct. The bristles at base of bill somewhat involving the 

 feathers are black, forming a narrow frontal line, not seen in the other. The 

 most striking difference is in the rump and upper tail-coverts, which are 

 always appreciably and abruptly lighter than tiie back, sometimes white or 

 only faintly glossed with plumbeous ; while in typical specimens of ludo- 

 vicianus these feathers are scarcely lighter at all, and generally more or less 

 varied with blackish spots at the end. The legs and tail are apparently longer, 

 the latter less graduated. These differences are, however, most appreciable in 

 specimens from the Middle and Western Provinces. Tiiose from tlie Western 

 States, east of the Alissouri Eiver, as far nortli as Wisconsin, are more inter- 

 mediate between the two, although still nearest to the Eocky Mountain bird 



