^j , r 11 E F A C E . 



be'niinino-. Like lengthened useless synonymy, such descriptions if possible should 

 be shunned. 



Humming-birds vary greatly in tlieir dimensions, even among members of the 

 same species, and therefore a specimen cannot be decided to be something else 

 because it does not agree exactly with the measurements of some described species, 

 to the eighth of an inch. The total length means from the point of the bill to the 

 end of the tail. Wing, from the shoulder to end of the longest primary. Tail, 

 from the termination of the caudal vertebrae to the end of longest rectrices measured 

 on top. Culmen, from the termination of the frontal feathers to the point. 



When considerable difference exists in the dimensions of the sexes, those of the 

 female are given as well as those of the male. In the majority of instances, how- 

 ever, they are too nearly the same to make it necessary that more than one should 

 be recorded, and then that of the female is omitted. 



The asterisk, placed before the names of certain species, indicates that it is not 

 contained in my collection. — Those who may possess any of these desiderata, and 

 are willing to dispose of them, would oblige me by informing me of the fact, as I 

 am naturally desirious of making the collection as perfect as possible. 



The drawings which illustrate the generic characters are, with but few excei> 

 tions, all made from specimens contained in my collection. 



D. G. E. 



