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Classification. — We will begin by getting well acquainted with the 

 various names under which the Carrot-Fly is known, and then we will ^ve 

 the indication of the place it occupies in Entomology. 



English names. — Carrot-Fly, Carrot Rust-fly. 



Scientific Latin name. — Psila rosse, Psilomyia rosae. 



French name. — Mouche de la carotte. 



Common French name. — Mouche a Carotte Manille. 



The Carrot-Fly is described as follows in its classification : Species, 

 Psila rosae; Genus, Psila; Family, Psilidae; Order, Diptera; Class, Insecta; 



Phylum, Arthropoda. 



Description. — The Carrot-Fly is about a quarter of an inch in length 

 and not quite half an inch from tip to tip of wings. Its narrow body is of a 

 metallic dark green, almost black ; the head is round, of ochre color ; the 

 eyes are red; the legs are ochre yellow. The wings are iridescent and 

 marked with ochre colored veins. The female has a long retractile ovipos- 

 itor, through which it deposits its eggs. The larva is easily identified. It 

 is a kind of a little apodous maggot, slim in shape, about a quarter of an 

 inch long, white or yellowish, shining, Avith a very small head furnished 

 with two black horny hooks with which it tears up the pulp upon which it 

 feeds. The posterior part of the body is truncite and rounded and has two 

 small black spiracles looking like two little horny tubercles. When the 

 larva are fully grown, they burrow into the soil and turn to pupoe. The 

 puparium is cylindrical, shining' and has a ferruginous or ochre-colored 

 tint. 



The nymphal stage, in the course of the summer season, lasts three or 

 four weeks ; but, if the transformation occurs in the fall of the year, the 

 pupje winter and the flies come out from them only in the following spring. 

 There are two generations in one season. 



Depredations. — Now that we are well acquainted with this foe of the 

 carrot, we will try to make out how it works injury to the plant it infests. 



We had a serious attack of this insect in our gardens below Quebec, 

 about fifteen years ago. But its depredations lasted only two years, and 

 now, it has reappeared during the last two years, being the cause of serious 

 damage, specially during the past summer (1909). This has decided me to 

 publish the present short article so that our gardeners may act in co- 

 operation to fight against it before it is too widelv distributed. 



