THE ROOT-FLY : DESCRIPTION AND NOTICES. 193 



flies arc not noted as causing any serious damage in this country, but 

 may be mentioned from their great resemblance to the common cab- 

 bage-fly." From the similarity in appearance and habits of the two 

 species, it would not be strange if the injuries of A. radicujii were 

 much more common than is generally supposed, and that much of the 

 damage ascribed to A. hrassicce in reality pertains to the former species. 

 Mr. Meade {loc. cit.) remarks of this species as follows : '' This ex- 

 cessively common little fly, which, as its name imports, feeds in the 

 larva state upon the roots of plants, especially those of the cabbage 

 tribe, is often confounded with other species. It may be recognized 

 by its projecting epistome [the lower face]; by the unequal sized scales; 

 by the thorax being black and marked in the male by two short, gray, 

 narrow stripes (rather than by three wide black ones, as is usually 

 stated) ; by the rather short, wide, somewhat pointed abdomen, with 

 a longitudinal dorsal black mark, crossed by three transverse straight 

 black lines, extending of an even width to the margin ; and by the 

 third and fourth longitudinal veins [see figure of venation, ante, for 

 position of these veins] being slightly convergent at their extremities." 



Briefly Noticed in this Country. 



The above meager account of this insect, which, from its specific 

 name, together with its habits, so far as known, should be of consider- 

 able economic importance, is all that can be compiled from the sources 

 at my command. While quite unsatisfactory, it may at least serve to 

 show our ignorance of the species, and incite to efforts for the attain- 

 ment of a fuller knowledge of it. 



Dr. Packaz'd's notice of " A. radicum" contained in his Report on 

 the Ilocky Mountain Locust {S^lli Ann. Rept. of the U. 8. Geolog. and 

 Geograph. Survey of the To'ritories, for 1875), is that of the radish- 

 fly, A. raphani, in acceptation of Dr. Fitch's belief in their being the 

 same. Of the figures given in illustration, on plate Ixiii, fig. 2, the 

 same as Fig. 54 above, the fly alone represents A. radicum, while a, 

 h and c, showing larva in double size, and pupa-case in natural size 

 and enlarged, are from Curtis' figures of A. hrassicm {h, to show the 

 natural size of the puparium, is very badly copied). The same figures 

 are introduced in the First Annual Report of the U. S. Entomological 

 Commission (p. 288, fig. 22, a, 5, c) to illustrate A. radicum. 



Mr. Glover {loc. cit.) refers to A. radicum as injuring radishes in 

 Europe. Dr. Fitch's notice of the species is limited to a comparison 

 of it with A. hrassicm, which has been quoted on a preceding page 

 (p. 186). 

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