268 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1946 
graphic sense—there are two areas of highlands, separated by the belt 
of lowland that crosses the isthmus along the Rio San Juan and Lake 
Nicaragua. As with so many other birds of corresponding range, the 
quetzal shows geographic variation on the two sides of the gap. The 
northern form (P. m. mocinno) is distinguished by the greater length 
of its upper tail coverts; it ranges from Chiapas to northern Nicaragua. 
The southern race (P. m. costaricensis) dwells in the mountain complex 
of Costa Rica and western Panama. Other members of the genus are 
South American. 
The quetzal is an inhabitant of forests of the Subtropical Zone. In 
Costa Rica, it is most abundant between 5,000 and 9,000 feet above 
sea level. Occasionally it is found as low as 4,000 feet; I have a record 
of a single bird at this altitude, but doubt if it often ranges lower. 
Where forests of huge oak trees extend up to nearly 10,000 feet in 
the Costa Rican mountains, it is not impossible that the quetzal accom- 
panies them, although definite records appear to be lacking. In Guate- 
mala, farther from the Equator, the northern winter makes itself 
felt and the Temperate Zone replaces the Subtropical at a lower alti- 
tude. Here the quetzal does not, at least at the present time, appear to 
extend upward beyond 7,000 feet. The dense human population of the 
central highlands may well have been responsible for the bird’s dis- 
appearance from the few possibly suitable forests that remain above 
this altitude. With one exception, all the other Central American 
members of the trogon family dwell at altitudes lower than the quetzal, 
although a few, as the Jalapa collared trogon (Z'rogon collars puella, 
and Z'rogon aurantiiventris, which seems to be a mere color phase of 
this species) overlap its range from below. The Mexican trogon 
(7. mexicanus) is characteristic of the Temperate Zone in Guatemala 
and extends higher than the quetzal. 
The forests in which the quetzal dwells are composed of crowded 
lofty trees, those that form the canopy ranging from 100 to 150 feet 
and even more in height. Oaks of a number of kinds occur throughout 
the quetzal’s altitudinal range, but they are more abundant toward its 
upper limit, where with huge boles and spreading crowns they domi- 
nate the woodland. Alders (Alnus acwminata) are abundant in many 
places, becoming nearly as tall, although not so massive, as the oaks. 
But more important for the quetzals are the numerous members of the 
laurel family (Lauraceae), including the wild relatives of the avocado 
(Persea spp.) and species of Vectandra and Ocotea—variously called 
ira and guizarré in Costa Rica, tepeaguacate in Guatemala—whose 
fruits are an important food of our birds. These forests are watered 
by abundant rainfall, and at all seasons they are bathed in cloud-mist 
much of the time. The constant moisture favors the development of 
an epiphytic vegetation of whose proportions one can hardly form a 
