Vol. XXX] ENTOMOLOGICAL NEWS 7 



angular. Antennae, legs and body with a moderate number of short 

 medium hairs. 



Measurements. Length of body, 1.8 mm. Length of antennal seg- 

 ments, III, 0.37 mm.; IV, 0.166 mm.; V, 0.187 mm.; VI, 0.187 mm - 

 Total length, 1.02 mm. Beak, III, 0.21 mm.; IV, 6.21 mm.; V, 0.07 mm. 

 Total length, 1.82 mm. Length of hind tibia, 1.36 mm.; hind tarsus, 

 0.083 mm. and 0.21 mm. 



EXPLANATION OF PLATES I AND II. 



PLATE I. A. Essigella calif arnica, alate viviparous female ; i. 

 wings; 2. cornicle; 3. head; 4. hind leg; 5. antenna; 6. rostrum. 



B. Essigella pini, n. sp., alate viviparous female; I, wings; 2. cor- 

 nicle ; 3. head ; 4. hind leg ; 5. rostrum ; 6. antenna. 



C. Unilachnus parnis, alate viviparous female; I. wings; 2. cor- 

 nicle ; 3. rostrum ; 4. antenna ; 5. hind leg. 



PLATE II. D. Eulachnus tlntnbcr<iii. n. sp., I. wing of male; 



2. antenna of male; 3. head of male; 4. head of oviparous female; 

 5. leg of oviparous female ; 6. antenna of oviparous female ; 7. rostrum 

 of male; 8. cornicle. 



E. Eulachnus rilcyi, alate viviparous female; i. wings; 2. cornicle; 



3. rostrum ; 4. head ; 5. hind leg ; 6. antenna. 



F. Larhnus junipcrirora, n. sp., alate viviparous female; I. wings; 

 2. cornicle ; 3. rostrum ; 4. antenna ; 5. hind leg. 



On an Undescribed Species of Medeterus (Diptera, 



Dolichopodidae) . 

 J. R. MALLOCH, Urbana, Illinois. 



In the June number of Entomological News for 1918 

 (p. 216) Mr. W. Marchand described the larva and pupa 

 of Arg\ra albicans Loew, at the same time making some 

 pertinent comments on the paucity of our knowledge of 

 the life-history of the members of this family, and a sug- 

 gestion that the "cyclorrhaphous" form of opening in the 

 evacuated cocoon might indicate evolutionary relationships. 

 Unfortunately the latter contention cannot be maintained by 

 an examination of the facts. The cyclorrhaphous exit is 

 produced by orthorrhaphous insects through a turning move- 

 ment of the body, causing a cutting off of the cap of the 

 cocoon through the abrasion by the sharp cephalic thorns of 

 the material composing the cocoon. In Cyclorrhapha the 

 ecdysis is facilitated by the expansion of the ptilinum on the 



