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exclusive of the head, while the first eight abdominal seg- 
ments are divided by a transverse suture, so that there 
appears to be seventeen abdominal segments, the sutures 
appearing too distinct in the cut. Mr. F. G. Sanborn has 
reared the fly, here figured, from the worm. The larva also 
lives in rotten wood; it is too scarce to ever prove very 
destructive in houses. . 
One of the most puzzling objects to the collector of shells 
or insects, is the almost spherical larva of Microdon globo- 
sus Fabr. (Pl. 12, fig. 8; fig. 8 c, larva just before pupation ; 
&, puparium; s, spiracular tubercles; v, vent; b, anterior 
view of pupa case), which has been traced to its fly-state by 
Mr. F. G. Sanborn. 
The Syrphus fly, or Aphis-eater, deserves more than the 
passing notice which we bestow upon it. The maggot 
(Fig. 4, in the act of devouring an Aphis) isto Fig. 4, 
be sought for established in a group of plant- 2 
lice (Aphis), which it seizes by means of the 7} 
long extensible front part of the body. The 

low, resembling closely the wasps, and frequents flowers. — 
We have figured in the Naruratisr (p. 278) the singular 
Tat-tailed pupa-case of Eristalis, and now present the figure 
of an allied fly, Merodon Bardus Say (Pl. 12, fig. 10; a, 
Puparium, natural size). We will not describe at length 
the fly, as the admirable drawings of Mr. Emerton cannot 
fail to render it easily recognizable. The larva is much like 
the Puparium or pupa-case, here figured, which closely re- 
= Sembles that of Eristalis, in possessing a long respiratory 
filament, showing that the maggot undoubtedly lives in the 
Water, and when desirous of breathing, protrudes the tube 
Out of the water, thus drawing in air enough to fill its inter- 
nal respiratory tubes (trachee). The Merodon Nareissa, 
_ “80 reared by Mr. Sanborn, probably lives in the soil, or in 
Totten wood, as the pupa-case has no respiratory tube, hav- 
Mg instead a very short sessile truncated tube, scarcely as 
AMER. NATURALIST, VOL. IL 
