affectiiu/ Carrots and Parsnips. 
\77 
but they cannot leap (fig. 4) ; they are exceedingly transparent, 
so that every internal part is visible. The head is a black horny 
substance, which contains the mouth ; this is alternately thrust out 
and contracted with great activity, the tip forming a hook, the 
base being forked like two spreading black horsehairs ; the body 
is composed of 11 rings besides the head and tail, this being 
rounded and producing 2 little black horny tubercles (fig. 5) ; 
from these extend 2 somewhat parallel pale lines which may be 
traced to the head ; the intestines are also pale, but beneath the 
antepenultimate segment is a bag of reddish excrement, more of 
a purple tint than the carrot which it had been feeding upon 
(fig. 6, magnified). 
The pupa is cylindrical, horny, shining, and coppery-ochreous 
(fig. 7), finely striated in rings, and of a pale rusty colour at the 
extremities ; the head is sloped off very much, forming an oval 
concave lid, with a thickened margin, which lifts up to allow the 
fly to crawl out when it hatches, and in front are 2 minute black 
tubercles; the tail is rounded and furnished with 2 little black 
points (fig. 8, magnified). 
The fly which it produces belongs to the Order Diptera, 
the Family Muscid/E, the Genus Psila, and was named 
Ros^: by Fabricius,* being found probably by hiin sunning itself 
upon the leaves of rose-bushes, and unfortunately he was unac- 
quainted with its economy. 
Psila Ros.e, the Carrot-Fly. 
2. P. Rosae is shining, of a pitchy black, with a greenish tinge, 
and clothed with pale hairs (fig. 9) ; the head (fig. 10) is globose 
and rusty ochre, with a few bristles; eyes lateral, orbicular, and 
black after death ; on the crown is a black spot with little simple 
eyes in triangle ; the face slopes inward, and the two drooping 
horns are inserted under tlie projecting forehead ; the 3rd joint 
is oval and black at the tip, and on the back is inserted a pubes- 
cent ochreous bristle (fig.a); the trunk is oblong; the scutelliun 
is small, trigonate, and rusty ; the 6-joinied abdomen is rather 
small, oval, and conical at the apex in the female, and furnished 
with a telescopiform contractile ovipositor (fig. 11) ; the wings 
lie horizontally on the back when at rest, and extend beyond the 
tail, being ample, iridescent, with a yellowish tinge, and all the 
nervures are bright ochreous ; the poisers are small and whitish ; 
the legs are bright ochreous, ami pubescent ; the feet are 5- 
jointed, the basal joint very long, the .5th small, with 2 little black 
* ' Entomologia Systematica,' vol. iv. p. 356, No. 181. Curtis's ' Guide,' 
Genus 1303, No. 5. 
VOL. IX. N 
