NOTICE OF SOME ANTHOMYIANS MINING BEET LEAVES. 



During the month of August of the p;ist year (1881), my attention 

 was called to an unusual condition of the beet leaves growing in a 

 vegetable garden, in Middleburgh, N". Y. The leaves were said to be 

 infested by some insect attack to such an extent that they could no 

 longer be served upon the table for *' greens." On examination, a 

 large number of the leaves were found to be extensively mined in 

 blotches of various sizes and in irregular forms. Most of them had 

 been ruptured by the escape of the miner, leaving the blotch discol- 

 ored, shriveled, and in many cases torn, apparently by the subsequent 

 growth of the leaf. Others, smooth and unbroken, showed, in eleva- 

 tion, the general form of an active larva feeding within. 



The Larva. 



On removing portions of the tliin covering cuticle, the larva, evi- 

 dently belonging to the order of Diptera, or flies, were disclosed. The 

 date of my first observation of them was July 19th. They were then of 

 various sizes and in difPerent stages of growth. When taken from their 

 mines the largest were found to be about one-fourth of an inch iu 

 Q length, of a watery color, showing in their transparency the 

 ^ intestinal canal crowded with its contents. The rings of the 

 ^ body were illy defined ; the anterior end was produced in a 

 FiG.oS.- point, beneath which the forked black jaws were visible ; the 



Larva of ■ -, , i • p n i 



beet-leaf posterior end was truncate, beanng a lew small warts margin- 

 An^h"^ alb'j of which the two subdorsal (spiracular) ones were the 

 ^y^'^^- largest. The accompanying figure of the larva is from an 

 alcoholic specimen, which fails to show several of its characteristic 

 features. 



Method of feeding. — It was interesting to observe, by holding an in- 

 fested leaf to the light, the method of mining and the rapidity with 

 which it was executed. The anterior end of the larva, when feeding, 

 was extended in an acute point, from which the two black cutting 

 organs were protruded like a pair of nippers, the motions of which 

 were so rapid as to suggest the idea of greediness or long abstinence 

 from food, and extreme hunger. In excavating the parenchyma, the 

 extensile anterior portion of the larva permitted the jaws to sweep a 

 curve of an entire semicircle. 



Larvm first observed. — Thelarvsehad first attracted attention within 

 the leaves, as was learned upon inquiry, at about the middle of June. 

 As soon as they were brought to my notice (on the 17th of July), and 

 their interesting character ascertained, several of the largest, still 



