NORTH AMERICAN DIPTERA. 235 



l§ifi*alioiii.yia iioi'iniilsi Loew (PI. iii. fig. 16). 



Stratiomyia normidd Loew, Ciintui'. vi. 5. 



Stratiomi/ia quadrigemina Loew, Centur. vi, 4. 



Stratiomyia notafa Loew, Centur. vi, 18. 

 Length % 9 11-12 mm. % . — Face black, shining, with whitish pile. Antenuse 

 black. Thorax black, with long yellowish pile, thickest on the pleura^, : basal 

 half of the scutellum black, apical half and spines yellow. Abdomen black, 

 with the following markings of yellow : second segment with a large lateral tri- 

 angle, third with a narrow lateral margin (widest at the anterior angle) and a 

 transverse marking at the lateral posterior angle, fourth similar, except that the 

 lateral and lateral posterior margin is usually narrowly interrupted, it also has a 

 small doi-sal triangle at the posterior margin, fifth with a narrow lateral margin 

 (obsolete posteriorly) and a central dorsal line ; venter black ; segments with a 

 lateral and posterior margin of yellow. Femora black ; tips of the femora, tibise 

 and tarsi, yellow ; tibiiie with a medial band of brown. Wings brownish, hyaline, 

 veins red. 



9 . — Face black, whitish pile ; facial orbits and a subcordate spot below the 

 ocelli yellow; lower part of the occiput yellowish : yellow of the scutellum more 

 prominent. Abdominal markings similar, except that the lateral and lateral 

 posterior margin is usually interrupted on the third, and the lateral posterior 

 marking on the fourth are less prominent, and in some specimens almost wanting. 

 Femora and outer two-thirds of the tibise black ; the posterior tibise and terminal 

 joints of tarsi brownish ; tips of the femora, basal portion of the tibiae and the 

 first two joints of the tarsi, reddish; the color of the tibiae and tarsi are some- 

 what variable. 



Var. quadrigemiua Loew ( 1 ). — This i.s a color variation in wliich 

 the markings on the tliird segment are the same as those on the 

 second, that is, a hirge lateral posterior triangle. I have in my col- 

 lection a specimen that is intermediate between this and the typical 

 8. normula. A specimen in the Museum Comp. Zool. marked, " a 

 quadrigemina, norma or normuli, differs in the flavo-liimaculata," is 

 another of these intermediate forms. The male of *S'. normula is 

 similar to that of *S'. norma, but the latter may be distinguished by 

 the greater amount of yellow on the scutellum ; the presence (usually) 

 of a small dorsal triangle on the third, and more hirsute abdomen. 



Var. notata Loew. — In this variety there is a transverse marking 

 at the lateral posterior margins of both the second and third seg- 

 ments. There is also proportionately less yellow on the lateral mar- 

 gins, but with upwards of twenty specimens before me I can readily 

 connect it with the typical S. normula. The two forms were taken 

 on the same day by Mr. Wm. Brodie. 



Toronto, Ontario, July 8, 12 and 17 (Wm. Brodie) ; New York 

 (Osten Sacken); AgriculturalCollege, Michigan (Davis") ; Algon- 

 quin, 111., June 2 (Dr. Nason) ; Brookings, S. D. (^Aidrich) ; AVar 

 Bonnet Canyon, Neb. (Univ. Neb.). 



TRANS. AM. ENT. SOC. XXII. JULY, 1895. 



