Diptera 59 c 



Phormia terrae-novae Robineau-Desvoidy. 



Phormia lerrce-novce Robineau-Desvoidy. Essai sur les Myodaires, p. 467, 1830. 



Thirty-eight specimens with data as follows: sixteen specimens, Bernard 

 harbour, Dolphin and Union strait, Northwest Territories, June, July and August, 

 1915; one specimen, same locality, July 10, 1916; eight specimens, same locality, 

 June and July, 1916; three specimens, Nome, Alaska, August 24, 25, 1916; 

 five specimens, Teller, Alaska, July and August, 1913; three specimens, Collin- 

 son point, Alaska, June, 1914; two specimens. Demarcation point, Alaska, 

 May 13, 1914 (F. Johansen). 



Phormia caerulea, n. sp. 



Male and Female. — Dark metallic blue,, without pruinescence. Head 

 black, frons opaque, orbits slightly shining; third antennal joint sometimes 

 brownish; palpi j^ellow, usually fuscous at apices in male. Dorsum of thorax 

 with two slender, widely separated vittse on anterior portion mesad of dorso- 

 centrals. Legs black. Wings clear, slightly infuscated at extreme bases. 

 Squamae brown. Halteres fuscous, paler in female. 



Male. — Frons narrowest at centre, where it is one-fifth the head-width, 

 orbit at widest part, just below ocelli, narrower than interfrontalia; orbits 

 hairy, bristles differentiated but not very strong; arista rather short-plumed, 

 apical third bare; profile as in Plate VIII, figure 19. Thorax not so noticeably 

 depressed as in other species, the postsutural dorso-centrals sometimes well 

 developed, the posterior pair usually so; both spiracles very large, the prothoracic 

 one extending from close to upper margin of pleura to within a short distance 

 of coxa, the covering of both spiracles deep black; lower margin of anterior 

 spiracle with many long bristly hairs; upper calypter with long hairs on upper 

 side, when closed. Hypopygium small; fifth sternite as in terrce-novce. Legs 

 as in terrce-novce. Inner cross-vein very little proximad of apex of first vein; 

 outer cross-vein less distinctly curved than in terrce-novce ; fourth vein almost 

 rectangularly bent, usually with a short appendiculate vein at angle. 



Female. — Similar to the male in colour. 



Differs in structure by having the frons two-fifths the head-width, the orbit 

 half as wide as interfrontalia, with two distinct supraorbital outer bristles. 



Length, 6-8-5 mm. 



Type locality: Bernard harbour. Northwest Territories, May 24, 1915 

 (F. Johansen). Paratypes, same locality. May, June, and July, 1915, 1916 

 (F. Johansen). 



This species resembles Phormia terrce-novce very closely in some respects, 

 but is undoubtedly distinct. Zetterstedt described a species from Greenland 

 under the name groenlandica, which has been sunk as a synonym of terrce-novce. 

 As both species probably occur in Greenland it is not, possible to decide the 

 validity of the accepted - synonymy without an examination of the type of 

 Zetterstedt's species. 



The appended key gives a summary of the distinguishing characters of the 



species. 



KEY TO SPECIES. 



MALES. 



1. Eyes separated by a narrow line; anterior thoracic spiracle with yeUow-haired covering- 



flaps ■ ; regina Meigen: 



Eyes separated above by a space at least twice as broad as distance across posterior ocelli; 

 anterior thoracic spiracle with black-haired covering-flaps 2 



2. Narrowest part of frons about one-half as great as width of eye seen from above; anterior 



thoracic spiracle very large; outer cross-vein of wing very slightly cur ved. caeruZo, n. sp. 

 Narrowest part of frons not over one-fourth as great as width of either eye; anterior 



thoracic spiracle not very large; outer cross-vein of wing abruptly bent 



terrcE-novcB Robineau-Desvoidy. 



