Odonata from Ecuador. 33 
3. Adult (or semi-adult?). Wings having the slightest 
possible tinge of brownish; the inner margin com- 
mencing beyond the level of the arculus. Anterior 
without any opaque apical space; the pterostigma dark 
brown (but the margins of the nervules narrowly hyaline). 
Posterior with a small (4 mm. broad) milky-white (or 
yellowish) opaque apical space, in which the costal 
margin is slightly dilated. 
Neuration of both pairs black; whitish in the apical 
space of the posterior. Head black above (in one 
example the epistoma and the front of the head are 
wholly greenish, and the labrum yellowish; in the other 
the epistoma is black, and the labrum very dark oliva- 
ceous, with a narrow yellow anterior margin). Pro- 
thorax black, with a very narrow pale yellow margin, 
and a greenish yellow lateral spot on either side. 
Thorax black; a narrow yellow dorsal line; two greenish 
yellow humeral lines having their origin in an opposed 
sense, the upper very short, and scarcely overlapping 
the lower; sides and beneath yellow; a black lateral 
line not extending to the posterior legs; no pectoral line, 
but only two small black spots, one anteriorly, the other 
posteriorly. Abdomen bronzy black, with a narrow 
yellow lateral line extending the whole length (or to the 
6th segment only); 8th, 9th, and 10th segments bluish 
(wholly or in part) above, the 8th scarcely longer than 
the 9th. Appendages black, as long as the 10th seg- 
ment, stout, curved regularly inward at the tips. Legs 
yellow; a line on the femora externally and on the 
tibie internally, and the tibie totally, black. 
?. Unknown. 
Length of abdomen, male, 58—65 mm. Length of 
posterior wing, 44—48 mm. L[xpanse, 91—98 mm. 
This species is perhaps most nearly allied to M. 
astictus (of which I described the male in the Ent. Month. 
Mag., vol. xiv., p. 88). It differs especially in only the 
posterior wings having an opaque apical space, and in 
the presence of a pterostigma in the anterior (in astictus 
the male has no opaque apical space in either pair, and 
the pterostigma is scarcely indicated; the female has 
the apex of both pairs milky, and no pterostigma) ; also 
in the absence of a pectoral black line; in the shortness 
of the 8th segment of the abdomen, &c. Differs from 
Jocaste, and its race (?) sincerus, in there being no dark 
TRANS. ENT. soc. 1881.—PART I. (APRIL.) F 
