﻿Pittier: Genus Monopteryx Spruce 625 



I should not be surprised, indeed, if the name uacu ox iiaucu had 

 been misapplied, when used to designate a species of Monopteryx, 

 The fruits of the Venezuelan specimens are very much like 

 those of all Pterocarpus species, the wing embracing the whole pod 

 from its base to the end of the style, which, however, is on the 

 median line and does not project outside the margin of the wing 

 as in that genus. Besides, the seeds are apparently always single 

 on the median line of the pod, while in Pterocarpus they are either 

 single or in pairs, enclosed in a more or less orbicular pod, central 



In examining the leaves of my specimens I found on the main 

 rachis, between the insertion of the lateral leaflets and at the 

 base of the terminal leaflets, traces of glandular formations as 

 mentioned by Bentham. In M. angustifolia the leaflets are 

 distinctly alternate, whereas they are subopposite in my speci- 

 mens; in M. Uaucu they are trifoliolate, and said to be opposite 

 in the basal pair. 



In the absence of the fruit and of perfectly developed stamens, 

 the peculiar structure of the calyx as described above would 

 justify the placing of the genus Monopteryx in the Geoffraeineae, 

 with Coumarouna and Pterodon, with the difference that in the 

 former the two broadly developed lobules are adnate. But with 

 our present knowledge we are able to place it definitely in the 

 Pterocarpinae and next to Pterocarpus. 



The Venezuelan plant collected by me differs from both the 

 species discovered by Spruce in several characters, for which 

 reason it must be considered as new. From Monopteryx angusti- 

 folia it departs in having a larger number of leaflets (thirteen 

 instead of nine), in the greater development of the inflorescence, 

 and in the total absence of the three inferior teeth of the calyx. 

 Monopteryx Uaucu is clearly differentiated by its three-foliolate 



Following are the emended characteristics of the genus Mono- 

 pteryx and a description of the new species, M. Jahnii. 



Monopteryx Spruce em. 



Calyx turbinatus, tubo breve subbipartito; labium superius 



(e laciniis 2 alte connatis) maximum, complicatum, emarginatum, 



florem ante anthesin includens, inferius obsoletum vel (e laciniis 



