32 CALIFORNIA ACADEMY OF SCIENCES. [Proc. 3D Ser. 



Asyndetus Loew. 



This genus was separated by Loew ^ from Diafhorus and 

 made to include those species which have the posterior 

 cross-vein very near the base of the wing, the third vein 

 ending near the second, and the fourth vein bent downwards 

 with an interruption or attenuation in the angle near the 

 middle of its distal segment. These with several other less 

 important correlated characters appear to establish the 

 genus satisfactorily. The single species here added agrees 

 with the other described forms except in the structure of 

 the second antennal joint, which is like that of species of 

 Syntormon, overlapping the third joint on the inner side. 

 This character by itself, however, is hardly of sufficient 

 value to exclude the species from the genus Asyndetus. 

 The males of the described species may be distinguished as 

 follows: — 



1. Second antennal joint broadly overlapping the third on the inner 



side syntormoides, sp. nov. 



Second antennal joint of the usual form 2 



2. First joint of fore tarsi incrassated ammophilus Loew. 



First joint of fore tarsi not incrassated 3 



3. Second joint of fore tarsi with clavate yellow appendages. 



appendiculatus Loew. 

 Second joint of fore tarsi without such appendages 4 



4. Thorax vittate .fratellus Aldrich. 



Thorax without vittse interruptus Loew. 



35. Asyndetus syntormoides, sp. nov. 

 Plate II, Figs. 50-52. 



Male. Length 2.75-3 mm.; length of wing 2 mm. Head distinctly wider 

 than the thorax; eyes large; face broad, metallic green, thinly dusted with 

 white, concave near the middle. Antennae large, black; first joint cylindrical; 

 second joint produced into a thumb-like lobe overlapping the third joint on 

 the inside to a distance nearly equal to half its length; third joint large, nearly 

 three times as long as broad, of nearly equal breadth as far as its middle, 

 then tapering to a point, clothed with short gray pile and bearing a 

 dorsal arista covered with very short pubescence. Front large and broad, 

 bright metallic green, with golden reflections. Postocular cilia rather abun- 

 dant, black above, white below. Thorax, scutellum and abdomen dark metal- 

 lic green, the first with violet, the second with golden, the last with cupreous 



1 Cent. VIII, 58-59, pp. 148-150. 



