2 CALIFORNIA ACADEMY OF SCIENCES, [Proc. 3D Ser. 



Symfycnus. Loew's genus, Synarthrus, abandoned by more 

 recent students of the Dolichopodidas, is here reinstated 

 for a further group of species that do not seem to 

 belong to the European genus Syntormon. Several new 

 species have been added to well known genera, such as 

 Pelastoneurus, Medeterus, Campsicnemus and Hydrophones. 



Hygroceleuthus Loew. 



Since the publication of Loew's Monograph of the North 

 American Dolichopodidee, the list of species of the genus 

 Hygroceleuthus has received several additions. Loew knew 

 only one North American species, H. latifes, which seems 

 to be the only representative of the genus in the states east 

 of the Mississippi. Osten Sacken has added two Califor- 

 nian species, and more recently Aldrich has described two 

 others from Idaho and Dakota, respectively. In the present 

 paper two new species are added, one from California and 

 one from Wyoming and Idaho. The following table will 

 aid in distinguishing the males of the seven species now 

 known : 



Middle tarsi compressed laterally 2 



Middle tarsi not compressed laterally 3 



Hind tibiae tipped with black Aldrichii, sp. nov. 



Hind tibiae yellow throughout latipes Loew. 



Wings very broad, narrowed towards the base 4 



Wings not very broad, with distinct anal angle 5 



Cilia of tegulae small, yellow crenatus O. S. 



Cilia of tegulse long, black consanguineus, sp. nov. 



Sides of second abdominal segment with tufts of yellow hairs . 



afflictus O. S. 



Sides of second abdominal segment without such tufts 6 



6. Cilia of tegulse small, pale idahoensis Ald. 



Cilia of tegulse long, black ciliatus Ald. 



I. Hygroceleuthus latipes Loew. 



This species is very common in meadows in Wisconsin 

 and Illinois during June, July and August. Aldrich men- 

 tions it from South Dakota, Wyoming and Connecticut. 

 He has also sent me a specimen from Moscow, Idaho. 



