142 



THE AMERICAN ENTOMOLOGIST. 



rapidly. Down the stems aud jar they would 

 come, and wander about over the paper on 

 which the jar stood. I then consulted the books, 

 and found that " the insect attaches itself by a 

 glutinous secretion to the leaves and stems of 

 plants ; its body then contracts and hardens, and 

 the insect assumes the pupa state within the 

 larva skin." So I returned them to the plants ; 

 I wished them to be scientific larv£B, and did n't 

 the books say they assumed the pupa state on 

 the leaves and stems? But it was of no use, as 

 fast as I returned them, down they would come. 

 Tliey were determined not to be scientific. So 

 I gave them a little box of earth into which 

 they immediately disappeared, where they as- 

 sumed the pupa state; and in about a week 

 thereafter, the perfect insects — the beautiful 

 Syrphus-fiies — made their appearance.* 



[•The great bulk of the Syrphus larvx with which we ai 

 acquainted fasten themselves to the leaves and stems i 

 ijlants, liefore cmtractin^' tn ijiipii', l>ut sonu- li:ive lnu); bw 



delphicus, are wholly Inivous), and ni tlK- i>rusi-iii-f ol a 

 blackish spot juat above the base of the atiteuuio. i>ur spe- 

 cieji also comes near the S, concava of Say, but the antenna; 



In two or three instances the rightful tenant 

 did not come forth from the Syrphus pupa; 

 but an entirely different four-winged, sprightly 

 busy-body had killed the owner aud taken pos- 

 session of its house. This was all plain to me, 

 for I had caught the busy Ichneumon in the act 

 of depositing her eggs in Syrphus larva^ while 

 the latter were engaged in feeding upon the 

 plant-lice. 



There is another enemy of the plant-lice, a 

 minute Ichneumon [doubtless some species of 

 Ajihidius — Ed.] which causes greater conster- 

 nation among them than all of their other foes. 

 The Syrphus picked his victim off so quietly 

 that it never seemed to dream that danger was 

 near, until it was kicking on the end of his pro- 

 boscis. But this very tiuy Ichneumon, even 

 smaller than its victim, would set a whole colony 

 of plant-lice on a stem in commotion. Bringing 

 iny lens to bear upon such a stem, I invariably 

 found the author of the mischief perched upon 

 the back of an unlucky plant-louse, which was 

 vainly endeavoring to dislodge her 'by kicking 

 aud throwing back its antenna-. But she was 

 usually too firmly seated to be unhorsed, and 

 patiently waited until quiet was restored, when 

 she would introduce her ovipositor in the back 

 of the plant-louse and leave an egg to hatch into a 

 tiny larva which should finally eat into the vitals, 

 causing a slow and lingering death. After the 

 Ichneumon had deposited her egg, she quietly 

 dismounted and proceeded to another plant- 

 louse, which would in the same manner become 

 restive, and again the alarm would be commu- 

 nicated to all on the stem. They would hold 

 on to the stem by their beaks, aud kick, and 



duce flies soon ai 

 transform on th. 

 which are hatched 

 to pass the wii 

 to transform? 



