E. B. WILLIAMSON 
211 
THE GENUS NEONEURA (ODONATA) 
BY E. B. WILLIAMSON 
The present paper is the outcome of an effort to identify ma- 
terial collected in Guatemala, British Guiana and Trinidad by 
B. J. Rainey, L. A. Williamson and myself. When Dr. Calvert 
learned I was studying this material he kindly offered me ma- 
terial and notes collected by himself in Costa Rica, informing 
me that his material included one probably new species. This 
species proved to be the same as one we had collected in Trinidad, 
and it is described and named in this paper. Through the good 
offices of Dr. Ris, I obtained drawings from M. iMenger of species 
in the de Selys collection. Unfortunately since de Selys’ work 
was done, the Neoneura specimens in his collection have been 
greatly damaged, and only a limited numljer could be figured. 
I have also, through the kindness of Dr. Calvert, Mr. Kahl, 
Dr. Henshaw and Professor Needham, been able to study the 
Neoneurae in the several collections in their charge, so that I 
know at first hand all the species but waltheri and rufithorax, 
neither of which, most unfortunately, IMenger could figure. The 
figures of appendages and thoracic patterns which accompany 
this paper, except where otherwise indicated, have been made by 
Mr. Kennedy, whose aid is gratefully acknowledged. The wing 
photographs were kindly made'for me by Mr. iMunz. 
De Selys’ separation of Neoneura into two groups on the basis 
of abdominal coloration served some purpose in identifying 
material, but gives no hint of relationships, since some of the 
closest allies are thereby separated. Real relationships are in- 
dicated, I believe, by the male appendages, and, to a lesser ex- 
tent, by female thoracic color patterns and prothoracic hind 
lobes, but the females of several species are not known at this 
time. i\Iy ideas of relationships are indicated in the key to 
males and the sequence of sjiecies in the text. 
The most valuable specific characters are found in the male 
aiipendages and the prothoracic hind lobes of the females. In 
the latter ca.se it must be noticed that in those species in which 
lateral developments of this border occur, these developments are 
TUANS. .A.M. ENT. SOC., XLIII. 
