260 Mr. 0. Salvin 07i the 



raise an hypothesis on this subject upon the facts that I have, 

 up till now, collected, but merely state the numbers, and wait 

 for further investigations. 



1. Phaethobnis adolphi. 

 Cohan, Vera Paz. November 15th. 



Though not common about Cohan, this species seems pretty 

 generally dispersed. Like many others, it feeds among the 

 Salvia. To a practised ear its presence may be detected by the 

 peculiar hum of the wings. This at once warns the collector 

 to look out sharply among the lower branches and flowers, 

 which are well searched by this bird, while the upper shoots of 

 the bush are comparatively neglected. At Yzabal, where P. 

 adolphi abounds, its habits somewhat differ. This is probably 

 owing to the very different nature of the plants from which it 

 takes its food, rather than to any other cause. If the females 

 are to be distinguished from the males by their yellower throat, 

 the ratio of the sexes is two females to seven males. 



2. Campylopterus delattrii. 

 Cohan, Vera Paz. November 1859. 



The large size and showy tail of this Humming-bird make it 

 one of the most conspicuous when on the wing. It is common 

 at Coban, feeding among the Salvia. It is said also to be found 

 in the Volcan de Fuego, but I have not yet met with it. The 

 females of this species are most abundant, their ratio to the males 

 being as five to two. C. delattrii is not nearly so shy as its 

 congener, C. rufus. 



3. Campylopterus pampa. 

 Coban. November. 



A single female specimen only was brought to me while at 

 Coban. 



4. Petasophora thalassina. 

 Volcan de Fuego. September 6th. 



The barrancos of the Volcano are favourite resorts of this 

 species. 



Dueiias, September 15th. A specimen obtained on this day 

 is the only one I have seen out on the llano, as the bird is 

 usually found in the dense forest. 



