214 LANIID^. 



Collyrio excubitorides, Baird^ U.S. Bound. Surv. ii. Birds, p. 11 '. 



Collurio excubitorides, Baird, Rev. Am. B. i. p. 445 °; Sumichrast, Mem. Bost. Soc. N. H. i. p. 548 ". 



Collurio ludovicianus, var. excubitorides, Baird, Brew. & Ridgw. N. Am. B. i. p. 421 " ; Lawr. Bull. 



Nat. Mus. no. 4, p. 18"; Mem. Bost. Soc. N. H. ii. p. 272". 

 Lanius Ivdovicianus excubitorides, Couesj B. Col. Vail. i. p. 561 ^^. 

 Lanius carolinensis, Wils. Am. Orn. iii. p. 57, t. 22. f. 5 ^' ; Sw. Phil. Mag. new ser. i. p. 368 " ; 



Licht. Preis-Verz. mex. Vog. p. 2, of. J. f. Orn. 1863, p. 58 ". 

 Lanius mexicams, Brehm, J. f, Orn. 1854, pp. 145, 148"; Scl. P. Z. S. 1859, p. 375"; Duges, 



La Nat. i. p. 141 '". 



Supra ardesiaoo-cinereus, uropygio paulo pallidiore ; capitis lateribus, alis et Cauda uigris ; scapularibus griseo- 

 albis ; secundariorum apicibus, speculo alari, subalaribus, rectrioibus quatuor gradatim lateralibus et corpora 

 subtus omnino albis ; rostro et pedibus nigris. Long, tota 8-0, alse 4-0, caudaB rectr. med. 4-2, reetr. lat. 

 3-4, rostri a rictu 0-9, tarsi I'O. (Descr. exempl. ex valley of Mexico. Mus. nostr.) 



Exempl. altera, supra grisescentior, uropygio fere albo, loris nigris supra albo indistincte limbatis. (=L,exeur- 

 bitorides, Sw., mas, ex Oaxaca, Mexico. Mus. nostr.) 



Eab. North Ambeica, Southern Atlantic and Gulf States ^ and Mississippi valley &c.^\ 

 Western United States and northwards to Saskatchewan ^ and Canada i*, Texas ^, 

 Mexican frontier^. — Mexico^ ^"^ ^^, Charco Escondido (Couch^), Mazatlan {Grayson^^, 

 Forrer), Presidio {Forrer), Colima {Xantus ^ ^^), Guanajuato (Duges ^), valley of 

 Mexico (White''), Tierra fria (le Strange), tableland (Bullock ^^), plateau, and 

 temperate region of Vera Cruz (Sumichrast^°), Mirador (Sartorius^), Oaxaca^ 

 (Boucard ^^), Tehuantepec city (Sumichrast ^^). 



For some time it was the practice of ornithologists to consider the Shrikes of the 

 south Atlantic States and those of Western and North-western America to be separate 

 species — the former bearing Linnseus's name L. ludovicianus i, the latter that proposed 

 by Swainson for a bird from the plains of the Saskatchewan, L. excubitorides. But 

 Dr. Coues, in his ' Birds of the Colorado Valley,' says that he has gradually become 

 satisfied that no distinct line can be drawn between these two birds, and that the two 

 alleged species grade into one another by insensible degrees ^*. Other authors hold 

 to these views, which we believe, so far as we can see with much more limited materials 

 at our disposal for forming an opinion, to be accurately true. We therefore consider 

 L. ludovicianus a variable species, with a tendency to become a dark race in the South- 

 eastern States and a lighter one in the West and North-west. In Mexico both races 

 occur ; whether as residents or migrants we are unable to say. One of our specimens 

 from the valley of Mexico seems to be in every way a typical L. ludovicianus. Our 

 other Mexican specimens are more of the L. excubitorides type, but are not very constant 

 in the tint of the grey of the upper surface or in the purity of the white of the rump. 



Though L. ludovicianus appears to be found throughout Mexico, it does not pass 

 beyond the limits of that country. It seems to be more common on the tablelands of 

 the interior ; but near Mazatlan and Tehuantepec it approaches the coast, but perhaps 

 only in the winter season ; for Grayson found Shrikes in the former district from October 



