Orth orrhapha brachycera. 



femora and tibiæ. Poulton records from England, in the work cited 

 several times above, T. pallipes \v\ih Liposcia discolor Marsh., T.cursi- 

 tans with Sciara sp. and Tachydromia sp., and T. minuta with 

 Alloxijsta sp. and fmally an undetermined Tachydromia with an 

 undeterminable fragmentary insect as prey. — Of several of the 

 species of Tachydromia the females are much more commonly met 

 with than the males. 



Of the genus about 137 species are known from the palæarctic 

 region; 33 have hitherto been found in Denmark, but of these two 

 are here described as new, the total number of palæarctic species 

 thus increasing to about 139. 



Table of Species. 



1. Thorax black, but covered by a more or less dense, 

 grey, brownish or yellowish pruinosity and not or 

 slightly shining; when so slightly pruinose that it is 

 black and shining {exigua), the antennæ are short 

 and the femora more or less black; (in the second 

 group with a shining thorax the antennæ are either 



long or, when short, the femora are yellow) 2. 



— Thorax yellow or black, shining, not pruinose 22. 



2. Thoracic and scutellar bristles yellow, thorax densely 

 pruinose 3. 



— Thoracic and scutellar bristles black, thorax less 

 densely pruinose; when the bristles are brown or 

 dark yellow {exigua) thorax is very slightly pruinose, 

 shining 20. 



3. Antennæ quite black 4. 



— Antennæ quite yellow or with the basal joints yellow. . . 9. 



4. All coxæ yellow 5. 



— Coxæ not quite yellow, more or less black; legs 

 obviously haired 6. fulvipes. 



5. Third antennal joint short, much shorter than the 

 arista; abdomen quite black or with grey bands only 



on the first segments 6. 



— Third antennal joint longer, twice or thrice as long 



as broad at the base and about as long as the arista. . . 7. 



6. Middle femora much thickened, tarsi black annulated; 



size 2,5—3,5 mm 1. fiavipes. 



— Middle femora less thickened, tarsi generally not di- 



stinctly annulated; size 1,8—2,3 mm 4. cothurnata. 



7. Third antennal joint long and narrow, thrice as long 



as broad at the base; tarsi not annulated 8. 



— Third antennal joint shorter, twice as long as broad 

 at the base; abdomen quite black; tarsi black an- 

 nulated 3. strigifrons. 



8. Abdomen with grey bands on all segments; middle 



tibiæ with a large spine; size 2,5 — 3 mm 2. maculip)es. 



