Diptera .-,!> < 



Phormia terrae-novae Robineau-Desvoidy. 



Phormia term-novae Robineau-Desvoidy. Essai sur les Myodaires, p. 467, 



Thirty-eight specimens with data as follows: sixteen specimen-. 

 harbour, Dolphin and Union strait, Northwest Territories, June. .July and At- 

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

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

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

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

 May 13, 1914 (F. Johansen). 



Phormia caerulea, ri. sp. 



MALE AND FEMALE. Dark metallic blue, without pruinescrnce. II..M 

 black, frons opaque, orbits slightly shining; third antennal joint sometime.- 

 brownish; palpi yellow, 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 I 

 Squamse 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; orbit - 

 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. hegs 

 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 yellow-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. 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 curved. caerula, 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-novce Robineau-Desvoidy . 



