List of a Collection of Birds 



The precipitation by iron is nol reliable; nor by a salt of 

 lead, dependent, as it is, on circumstances over which we have 

 nor always control. I should, therefore, in all ordinary cases, 

 recommend the use of magnesia mixture as a precipitant of 

 tribasic phosphoric acid, and it is hardly necessary to say that 

 the results will be good, if the mixture has been properly 

 pn pared. 



VIII. — List of a Collection of Birds from Northern Yucatan. 



By Geo. N. Lawrence. 



I „! May LOth, 1SG9. 



Di ring the year l v <'>.~> Sefior Jose Salazar Ylarregui, then 

 governor of the province of Fucatan, began the important 

 enterprise of a complete Burvey of the country, in regard 

 both i" its physical and natural history. As the Mexican 

 Commissioner of the CTnited States and Mexican Boundary 

 Survey, Governor Salazar was well known in the United States 

 a- an accomplished astronomer and geographer, and his experi- 

 ence in the former work was an earnesl of Buccess in his new 

 undertaking, [nviting \>v. Arthur Schott, of Washington, to 

 conned himself with the survey as naturalist, an arrangement 

 was made by Governor Salazar with Professor Henry, Secre- 

 tary of the Smithsonian Institution, to Bend all the collections 

 to hi- care for identification, and the ultimate preparation of a 



report 



The survey was fully organized, and commenced it- opera- 

 lions with -rcat success, and continued until L866, when the 

 change in the affairs of Mexico prevented all further proceed- 

 ings, and the work was broken off without any prospect of 

 apeedj resumption. Many valuable collections were however 

 made during the progress of the work, and transmitted to 

 \\ ashington : and having had those of the birds intrusted to me 



