RIEFFER'S HUMMINGBIRD 433 



family most numerous in the cultivated areas of the humid Carib- 

 bean lowlands. Thus Charles W. Riclimond (quoted by Bendire, 

 1895) wrote that it "is extremely abundant in the lowlands of eastern 

 Nicaragua. It outnumbers in individuals all the other (five) species 

 of Hummingbirds found in the same region. On the Escondido 

 River this species is confined to the banana plantations and the shrub- 

 ber}'^ around the houses, where it finds an abundance of food and good 

 nesting sites. It is the plantation Hummer, only two other species 

 occasionally wandering into the plantations from the forest, wliich is 

 the home of the other species." Similarly George K. Cherrie (1892) 

 affirms that in Costa Rica it is "the most abundant species about San 

 Jose, and indeed the most abundant species found on either 

 coast." This is certainly true, in my own experience, of the Carib- 

 bean coastlands of Costa Rica; but on the Pacific side of the 

 country Rieffer's hummingbird is abundant only in the more 

 humid regions from the Gulf of Nicoya southward. About the shores 

 of the Gulf it mingles with the related cinnamomeous hummingbird 

 {Ainazilia cinnmnomea) ^ and along the Pacific side of Central 

 America to the northward, where the dry season is long and severe, 

 it is entirely replaced by the latter species, which here is almost as 

 familiar and abundant on the plantations, in the flower gardens, and 

 in the light, open woodlands as its green-breasted relative on the 

 opposite coast. 



A bird of the clearings, Rieffer's hummingbird is found in the forest 

 only in the more open glades and seldom far from its edge. While 

 most abundant in the lowlands, it extends upward into the highlands 

 to an altitude (in Costa Rica) of about 5,000 feet and (on the author- 

 ity of Mr. Cherrie) is found occasionally as high as 6,000 feet. 



Courtship. — No hummingbirds, so far as we know, actually assoc- 

 iate in pairs; and the male never joins a female in the duties of 

 a nest. The purpose of the male's courtship, then, is to effect tem- 

 porary union with the female, resulting in the fecundation of the 

 eggs, not to attach unto himself a mate. Two strikingly different 

 modes of courtship are found in this great family, and may be 

 characterized as "dynamic" and "static." In the former, well ex- 

 emplified by the broad-tailed hummingbird {Selasphorus platycercus) ^ 

 the male gives a thrilling aerial display, which centers around the 

 female, rising high into the air and swooping down in front of her 

 as she perches, swinging back and forth in a great, open U, the arms 

 of which may be 50 or 60 feet high. In the "static" courtship the 

 male establishes his headquarters in one particular spot, where he is 

 to be found day after day during the breeding season. Usually he 

 has a favorite perch, where he rests to deliver untiringly the calls, 

 frequently weak and unmelodious, which draw the females' atten- 



178223—40 34 



