AGROMYZID LEAF MINERS — FRICK 425 



Phytomyza plumiseta Frost (part), Mem. Cornell Univ. Agr. Exp. Sta., vol. 78, 



p. 87, 1924 (specimens from Aquilegia sp.). 

 Phytomyza aquilegiana Frost, Ann. Ent. Soc. Amer., vol. 23, p. 459, 1930 (figures 



of puparium and mined leaves). 



The holot3rpe male is in the U. S. National Museum (No. 50023). 

 This is a common species that is similar to Phytomyza angelicella in 

 having a j^ellow frons, dark third antenna! segment, mesonotal 

 margins, scutellum, and femora, and the dorsal upper-orbital usually 

 shorter than the ventral (fig. 141). The length of this seta is variable 

 and it varies from as long as the ventral upper-orbital to three-fifths its 

 length. There is usually a very small third lower-orbital and the 

 genovertical plates are yellow (fig. 141), The mesonotum bears four 

 to five rows of acrostichals, and the intraalar row has numerous 

 setulae (10 to 12 anterior to the suture and 13 to 15 posterior to it). 

 The larvae form blotch mines in the leaves of Aquilegia spp. and 

 Thalidrum spp. I have seen specimens from California, Washington, 

 Idaho, Pennsylvania, and New York. 



Phytomyza atricornis Meigen 



Phytomyza atricornis Meigen, Systeroatische Beschreibung der bekannten 

 europaischen zweifliigeligen Insekten, vol. 7, p. 404, 1838. — Hendel, in 

 Lindner, Die Fliegen der palaearktischen Region, fam. 59, p. 353, 1934 

 (figures of head and wing). 



Phytomyza chrysanthemi Kowarz, in Lintner, Report of the State Entomologist, 

 in 44th Ann. Rep. New York State Mus., p. 243, 1892. — Smulyan, Massa- 

 chusetts Agr. Exp. Sta. Bull. 157, p. 21, 1914 (figures of all instars and 

 mined leaves). 



This species is probably the most widespread and omnivorous in 

 the Agromyzidae. It has the frons yellow, third antennal segment, 

 mesonotal margins, scutellum, and femora dark, and both upper- 

 orbitals of equal length and strength. The mesofacial plate may be 

 dark or it may be yellow with the subantennal grooves dark. There 

 is only one lower-orbital. The acrostichals are frequently absent 

 but some specimens have one to four. The larvae form serpentine 

 mines in the leaves of many plants. There are 27 larval host plants 

 listed in the table at the end of this paper. Nearly 300 more larval 

 host plants are known in Europe (Hendel, 1934). I have seen reared 

 specimens from California, Oregon, Washington, Massachusetts, and 

 from British Columbia. 



Phytomyza atrlpalpis Aldricli 



Phytomyza atripalpis Aldrich, Proc. Ent. Soc. Washington, vol. 31, p. 89, 1929. 



This is a moderately large species (2.25 mm. in wing length) that 

 has the frons yellow, the thu'd antennal segment, mesonotal margins, 

 scutellum, forecoxa, and femora dark. The two upper-orbitals are 

 of equal length and strength (fig. 142) and the mesonotum has two 



