3 io 
The Ohio Naturalist. 
[Vol. XIV, No. 7, 
The Egg. Figs. 3 and 4. 
The egg is cylindrically oval, slightly narrowed posteriorly; 
dorsal side, concave; ventral side, convex; lateral sides, somewhat 
parallel. A gelatinous cap covering the micropyle is situated up¬ 
on the anterior end. Length .68 mm to .75 mm. Width .18 mm 
to .2 mm. (10 eggs). 
The chorion is smooth, partially transparent, pearly white. 
A delicate mosaic work of regular pentagonal facets was observed 
upon a small portion of the chorion of one egg. The others were 
covered with some material which probably obscured the sculptur¬ 
ing. 
In the breeding jars the eggs were found on bacon, sweitzer 
cheese, ham and slightly putrid beef-steak, rarely in clusters, be¬ 
ing, as a rule, scattered singly over the surface pointing in various 
directions. No eggs were ever found upon the sides of the jars. 
Duration of the egg stage 23 to 54 hours. Temperature range 
60° to 80° F. Normal saline solution will hasten the hatching 
process. The chorion collapses after the larva emerges. 
The Larva. Figs. 6-14. 
The Larva may be observed through the partially transparent 
chorion several hours before hatching. When ready to emerge 
the anterior end of the egg shell is pulled back slowly, receding about 
4 jd r, and is then suddenly shoved forward. After several of these 
backward and forward movements, the egg-shell splits across 
the anterior end and back on the sides a distance of about .2 mm. 
(Fig. 5.) Through the opening thus made the larva emerges. 
The larvae are active immediately after they emerge from the 
shell. 
The newly hatched larvae measure, when fully extended, from 
.8 to .88 mm. long; when contracted .7 to .75 mm. long. Width 
.1 to .15 mm. To the unaided eye, the young larvae, except for 
the black chitinous mouth parts, are white. Under the binocu¬ 
lar they have a dusky granular appearance. Through the partial¬ 
ly transparent integument the two main tracheal tubes, for their 
entire length, are visible. 
In shape, the larvae are cylindrical, blunt at the posterior end, 
tapering gradually toward the anterior end. The segments are 
as distinct and of the same number as in the mature larvae. The 
integument is smooth and devoid of vestiture, except for three 
faint transverse, irregular rows of black chitinous teeth or spines 
on the antero—ventral portion of each of the 7 segments, posterior 
to and including the sixth segment. 
The cephalic segment is bilobed, each lobe bearing on its 
antero—dorsal surface an antennal tubercle. Between the oral 
lobes extend the paired falcate mouth-hooks. The cephalo- 
pharyngeal skeleton extends nearly the length of the first two 
