AMERICAN DIPTERA. 51 



abdomen in my specimens is brownish red, third to fifth segments in 

 male deeper reddish brown and shining, fonrth and fifth segments 

 and posterior margin of third in female shining deep green. One 

 male from Cinchona has the fourth segment with a metallic bluish 

 reflection. First and second segments quite uniformly opaque brown- 

 ish red, only faintly lighter on each side of middle. The cross-band 

 of anterior margin of third segment is very finely interrupted in 

 middle, showing only a very delicate thread of red, in one female 

 hardly apparent, but emarginate behind. This band in the male 

 widens laterally, not so in the female. Lateral spot of yellow pile 

 of fourth segment a little larger in the male. Front femora of male 

 not thickly black pilose on posterior side like the middle pair. Wings 

 are smoky hyaline, slightly flavous on anterior border, more deeply 

 and widely so toward base of wing, distally filling only the fourth 

 costal cell ; spurious vein on its middle appearing enlarged, as though 

 fractured, with a slight cloud. Otherwise agreeing with Williston's 

 description of his Santo Domingo specimens. 



A character of the wings in this genus, which seems to have been 

 overlooked, is the presence of an extra cross-vein, forming a fourth 

 costal cell. It is not mentioned by Macquart, Loew, or Williston. 

 This extra cross-vein takes the place of the stigma, which is entirely 

 absent, and joins the auxiliary vein a little before its tip with the 

 first vein. The original third costal cell is thus formed into tw'o 

 cells. This is plainly shown in all of my specimens, as is also the 

 peculiar swollen and clouded middle of the spurious vein. 



There is an approach to this extra cross- vein in some specimens 

 of EriMalis, the proximal portion of the stigma in the right wing of 

 a specimen of E. flavipes var. melanostomus from Colorado almost 

 appearing like a cross-vein. It seems apparent also in an unspurred 

 male of Mallota cimbiciforyriis, from Washington, T>. C. Williston 

 figures the wing of Pter. crucigera in his monograph, but the figure 

 indicates rather a small stigma than a cross-vein. 



Mr. Cockerell has mentioned this species on p. 74 of Jour. Inst, 

 of Jamaica as sent from Bath (Swainson). 



Note. — The same swollen middle of the spurious vein is to be 

 seen in many other Syrphidae, as Spilomiiia, etc. 



The genus Pferoptlla Lw. is a synonym of Meromacriis Rdi. (see 

 Williston, "Ent. News," xVpril, 18'93). ' 



61. Helophilus aureopilis n. sp. aif. flarifacies Bigot. 



Length 10 mm. — Face, cheeks and h)wer half of front wholly light yellow and 



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



