364 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1924 



Somewhat suggestive of the Brassavolas is Brassla longissima 

 (pi. 6, fig. 1), another lowland species. The flowers are greenish 

 with a yellowish tinge, the lip dotted with purple. The plant is 

 curious because of the unusual elongation of the sepals, these often 

 attaining a length of 7 to 8 inches. 



Chondrorrhyncha lipscombiae (pi. 26, fig. 1) is an attractive plant, 

 suggesting the Trichopilias that are so common in Costa Rica. It is 

 a species known only from Gatun Lake. The flowers are white, with 

 a lavender band around the edge of the lip. 



Plates 7, 8, and 9 show several Panama species of Epidendrum. 

 This is the largest genus of American orchids, and is confined to the 

 Western Hemisphere. About 750 species have been described, some 

 of them ranging as far north as Florida. There are many species in 

 Panama, and they exhibit great diversity in the form and color of 

 their flowers. Epidendrum atropurpureum (pi. 7, fig. 1) is a coarse 

 plant with rather few but large and showy flowers, the sepals and 

 petals being dark purplish and the lip white, with purplish lines in 

 the center. It is plentiful on the dry Pacific slope of Costa Rica, and 

 blossoms during the dry season. I have seen handsome color vari- 

 eties of it also in Salvador. 



Several species of Mormodes are found in Panama. The ones 

 illustrated (pi. 10, pi. 11, fig. 1) have brown flow^ers of thick texture 

 and striking appearance, remarkable more for their oddity than their 

 beauty. These plants are noteworthy for the fact that they shed 

 their leaves during the dry season, at which time the flowers are 

 produced. 



The same habit prevails in a related genus, Catasetum (pi. 11, fig. 

 2, pi. 12). The species illustrated is a rather attractive plant, with 

 greenish white, fragrant flowers. In this group there are two kinds 

 of flowers, staminate and pistillate (sometimes termed male and 

 female), of quite different appearance. In Cycnoches (pis. 13, 14), 

 too, flowers of two sexes, unlike in appearance, are produced. The 

 sepals commonly are green or greenish, and the lip white. These 

 plants, like those of related genera, are frequently or usually devoid 

 of leaves at time of flowering. 



In the case of many of these orchids that have large bulbs 

 (pseudobulbs), organs for storage of moisture, and are leafless 

 when the flowers are unfolded, the bulbs are hollow, at least with 

 age, and inhabited by colonies of characteristic ants that bite 

 severely when the plant is molested. For this reason it is far from 

 pleasant to collect them. The function of the ants is not well under- 

 stood. Certainly they are not necessary to the growth of the plant, 

 for Mr. Powell states that when preparing plants for the garden, 

 the ants are always removed, notwithstanding which the plants con- 

 tinue to grow luxuriantly. 



