THE CANADIAN ENTOMOLOGIST. 103 



found abundantly, singly and in clusters, particularly where the cover 

 touched the top of the jar. The short time required for the production 

 of so many individuals was surprising. I half filled a covered tumbler 

 with the pickled raspberries and larvae, and they continued to produce 

 flies for several weeks. I regret not having more attentively observed the 

 exact time required for the different stages, and can only say that its 

 growth from the egg must be very rapid, and its pupal state does not last 

 longer than ten or twelve days. 



The larvae, when full grown, are nearly one-fourth of an inch long, 

 somewhat tapering towards the head, which is small ; and are sparsely 

 covered with minute hairs, particularly on the divisions of the segments. 

 They have no feet, but can travel quite rapidly on glass, seeming to retain 

 their hold by a glutinous condition of the skin, and moving by extending 

 and contracting their bodies. They seemed to exist with ease either in 

 the vinegar or the air, moving through the former in search of food, and 

 sometimes coming out of it, and either resting or moving about on the 

 glass sides of the vessel. Their bodies were quite transparent, and under 

 the microscope their internal organs could easily be seen. At both ends 

 of their bodies are curious projections or tubercles, which are also seen in 

 the pupa. 



The puparium is about three-sixteenth inch long, oval in shape, and 

 yellowish brown in color, with the tubercles at head and tail before 

 referred to. 



The fly measures about one-eighth of an inch in length, with a large 

 rounded thorax, long legs, and broad iridescent wings. The whole insect 

 is yellowish in color, and very hairy, even to the proboscis. Some of the 

 hairs on the head bear three or four branches. The wing forms a very 

 beautiful object for the microscope. 



Last year the flies were attracted to some raspberry wine in process of 

 fermentation, hovering about the jars and alighting upon the corks, evi- 

 dently seeking for an opening through which they might pass to lay their 

 eggs. It is doubtless in this way that fruit is attacked by this or some 

 allied species. The minute fly effects an entrance beneath a not closely- 

 fitting lid, and deposits its eggs on the fruit, or upon the side of the jar, 

 whence the young larvae make their way to the fruit, or find their susten- 

 ance in the liquid. 



During the past summer I was desirous of again testing the matter. 

 A few raspberries, with a small quantity of vinegar, placed in a pickle 



