1933 ] 
Notes on American Trypetidze 
55 
dentations. There are various hyaline spots on the base of 
the wing. The cross-veins are approximated, parallel; the 
third vein is spinose for almost its entire length. 
The abdomen is brown, sparsely covered with brownish 
hairs. The ovipositor sheath of the female is dark brown, 
trapezoidal in shape. 
Total length, female, 4 mm.; length of wing, 3.4 mm.; 
length of ovipositor sheath, 0.6 mm. 
Described from 10 $ $ and 7 $ $ from Bartica, British 
Guiana, March, April, May and September, from the John- 
son Collection in the Museum of Comparative Zoology, and 
the collection of the Academy of Natural Sciences of Phila- 
delphia. The types are distributed as follows : holotype S 
and allotype $ , and 5 paratypes in the M.C.Z. ; 5 paratypes 
in the A.N.S.P. ; 2 paratypes in the United States National 
Museum ; 2 paratypes in the American Museum of Natural 
History; one paratype in the collection of H. K. Munro. 
This very interesting species agrees closely in structure 
with Tetreuaresta obscuriventris, except that it has two 
well developed upper orbitals, while only one pair is pres- 
ent in Loew’s species. The wing pattern is very like that 
of Xanthaciura, and there are some structural similarities. 
Genus XANTHACIURA Hendel 
Hendel, 1914, p. 86. (type, Trypeta chrysura Thomson). 
Tetraciura Hendel, 1914, p. 90. (type, T. quadrisetosa Hen- 
del). 
Eucosmoptera Phillips, 1923, p. 131 (in part; no type des- 
ignated) . 
The front is very narrow, naked ; there are three pairs of 
lower orbital bristles, but only one fully developed pair of 
upper orbitals ; the ocellars are well developed. The face is 
retreating ; the occipitals are white, stumpy. The dorsocen- 
trals are in front of the anterior supra-alars ; there may be 
one or two pairs of scutellars. The wings are narrow, the 
third vein naked. 
Eucosmoptera tetraspina Phillips may be taken as the 
type of her genus, as it was the species with which she was 
most familiar. There really seems to be no good reason for 
