SIALIA. 47 



appears it is very common throughoi^t the entire temperate region, ascending to a 

 height of 7400 feet above the sea. In Guatemala it is distributed over the table- 

 lands of the Cordillera, ascending as high as 10,500 feet. It breeds in the neigh- 

 bourhood of Duefias, as we more than once obtained young birds in their first spotted 

 plumage in August. The lowest district vrhere it is found is on the plains of San 

 Geronimo, where it also breeds, Mr. Owen having obtained its eggs in 1860. It is 

 also abundant in open places in Alta Vera Paz, having been noticed both at Tactic 

 and Coban. In Honduras, the most southern locality whence we have any tidings of 

 Sialia sialis, Mr. Taylor found it throughout the line of country he traversed, being 

 common amongst the pine trees of the high ridges ^^- 



In its migrations this bird would seem to be somewhat irregular, as it sometimes 

 makes its appearance in the United States in February, and even in the end of January 

 when the season is mild ^. It is resident in Bermuda ^^, but in Cuba of uncertain 

 appearance. A large flock. Dr. Gundlach tells us, arrived in April 1860 in the neigh- 

 bourhood of Havana ; but since then he has not observed it ^. 



2. Sialia mezicaua. 



Sialia mexicana, Sw. Faun. Bor.-Am. ii. p. 202 ' ; Scl. P. Z. S. 1856, p. 293 ', 1859, p. 362 ' ; Baird, 

 Eev. Am. B. i. p. 63*; Sumichrast, Mem. Bost. Soc. N. H. i. p. 544°; Baird, Brew. & 

 Eidgw. N. Am. B. i. p. 65 °; Lawr. Mem. Bost. Soc. N. H. ii. p. 267''; Coues, B. of the 

 N.W. p. 14'. 



Sialia cceruleicollis, Vig. ZooL Voy. Blossom, p. 18, t. 3°. 



8. siali similis, sed supra purpurascentius azurea, gula et abdomine medio caerulescentibus differt. Long, 

 tota 6-5, alse 4-5, caudae 2-8, rostri a rictu '75, tarsi -75. (Desor. exempl. ex Jalapa, Mexico. Mus. 

 nostr.) 



Hab. Westben Nokth Amekica, from Eocky Mountains to Pacific ^ ^. — Mexico ^ ^ (^Salle ; 

 le Strange), Saltillo (Couch ^), Mazatlan [Orayson''), plains of Colima {Xantus''), 

 Jalapa {de Oca ^), Popocatepetl (Sumichrast ^). 



In North-western Mexico Sialia mexicana would appear to be found at lower eleva- 

 tions than in Southern Mexico ; and this may also be said of it in the districts it 

 frequents in more northern countries. Dr. Cooper recording its abundance in all wooded 

 districts in California, except in the high mountains^. This species would appear 

 to be more stationary in its habits than the eastern species S. sialis, as Dr. Cooper met 

 with birds associated in flocks in Washington Territory in December, at a time when 

 S. sialis is to be found in much more southern countries ^. In its habits S. mexicana 

 resembles S. sialis ; but its song is described as far less tuneful ^. 



In Guatemala we never observed this species ; for though Bluebirds were obtained in 

 mountains over 10,000 feet above the sea, they proved to be of the eastern species. 



The Mexican Bluebird was described by Swainson, in a note in the ' Fauna Boreali- 



