436 PROCEEDINGS OF THE NATIONAL MUSEUM vol. io8 



yellow and the mesonotuin dull gray pollinose. This species is most 

 closely related to Phytomyza genalis but may be separated by P. 

 rufipes having the anepisternum three-fourths dull gray. The larvae 

 make serpentine mines in the leaves of various crucifers in Europe. 

 The seven North American specimens that I have seen were from 

 central Oregon. 



Phytomyza sphondylii Robineau-Desvoidy 



Phytomyza spondylii Robineau-Desvoidy ,'iRev. Mag. Zool., ser. 2, vol. 3, p. 400, 



1851. 

 Phytomyza sphondylii Robineau-Desvoidy, Hendel, in Lindner, Die Fliegen der 



palaearktischen Region, fam. 59, p. 483, 1935 (figures of head and wing). 



Since this Holarctic species was named for the first known larval host 

 plant, Heracleum sphondylium L., the proper spelling should be sphon- 

 dylii and not spondylii as originally proposed. Phytomyza sphondylii 

 is very similar to P. albiceps in having a yellow frons, dark third an- 

 tenna! segment, scutellum, and femora, and the mesonotum bordered 

 with yellow. From P. albiceps this species is distinguished by the 

 two developed upper-orbital setae (although the dorsal is shorter than 

 the ventral) and the anepisternum being three-fourths dark. I have 

 reared this species from serpentine mines in the leaves of Heracleum 

 lanatum Michx. in California. 



Phytomyza subtenella Frost 



Phytomyza subtenella Frost, Mem. Cornell Univ. Agr. Exp. Sta., vol. 78, p. 89, 

 1924. 



The holotype female is in the U. S. National Museum (No. 50021). 

 This species has the frons yellow, the third antennal segment, meso- 

 notal margins, scutellum, and femora dark, and the forecoxa distally 

 yellow. The upper-orbitals are equally strong and the acrostichals 

 are in two rows. From Phytomyza crassiseta this species can be sep- 

 arated by its having the first and second antennals yellow, the arista 

 not greatly expanded, and two strong lower-orbitals (fig. 166). From 

 P. plantaginis this species differs in having two strong lower-orbitals 

 and an inner postalar seta. The wing has M1+2 undulating and the 

 anal vein straight (fig. 167). At present known from two specimens 

 from Washington and Wisconsin. 



Phytomyza tiivittata Frost 



Phytomyza trivittata Frost, Mem. Cornell Univ. Agr. Exp. Sta., vol. 78, p. 89, 

 1924. 



This is a species of moderate size (1.75 mm. in wing length) with 

 yellow frons and scutellum and a dark third antennal segment. The 

 head is mostly yellow and has both upper-orbitals of equal length and 

 strength (fig. 168). The wing has the radial sector strongly curved 



