124 SEXUAL DIFFERENCES. 



the same time, by gentle management, it may be 

 reconciled and rendered happy, exchanging its 

 terror for familiarity. 



The Trochilidce are divided by modern orni- 

 thologists into numerous genera, of which fifty- 

 seven are enumerated by the Prince of Canino, 

 in his " Conspectus Grenerum Avium." In most 

 instances the generic characters are sufficiently 

 determinate, but that some genera will have to 

 be remodelled, is only what may be expected in 

 a group so abundant in species ; nor can it sur- 

 prise us if others be added from time to time as 

 our knowledge of these birds is increased by far- 

 ther research. 



We have already said, that as a general rule 

 the females differ so much in colour and style of 

 plumage from the males, that they might be (as 

 indeed they have been) mistaken for different 

 species. On the contrary, however, in some in- 

 stances the sexes resemble each other so closely, 

 that in order to denominate with certainty be- 

 tween them, dissection of the freshly-killed bird 

 is necessary. In cases where the sexes differ in 

 plumage it is not always very easy to distinguish 

 between an adult female and a young male of 

 the year. Sometimes, however, the young male 

 exhibits traces of future splendour which, to 

 the eye of the naturalist, are sufficient sexual 

 indications, although an ordinary observer would 

 overlook them. 



