2 BULLETIN 422, U. S. DEPARTMENT OF AGRICULTURE. 
DESCRIPTION. 
THE EGG. 
The egg (fig. 1) is ellipsoidal in shape and creamy white when firs 
deposited, later becoming brownish. Ten eggs gave an average 
length of 1.24 mm. , ranging from 1.16 to 1.30 mm., and an averse 
width of 0.67 mm., ranging from 0.62 to 0.76 mm. 
THE FIRST-STAGE LARVA. \ 
The general color is greenish white, with light, dirty brown head, — 
and with the tips of the mandibles and the claws dark brown. The 
head and legs are large and out of proportion to the rest of the insect. — 
The surface of the body is sparingly covered with short spines. Six- : 
teen pairs of branched appendages extend from the sides of the body, 4 
the branches being larger on the anterior pair. Another pair of long 
appendages originates on the dorsal surface of the body, Just anterior — 
to the anus, and it is upon this pair that the excrement and cast skins, ~ 
commonly known as the “pack,” are carried, the pair 
of appendages sometimes being called the“feecifork. va 
The length of the first-stage larva, including the head, 
is about 1.5 mm. and the width of the head about — 
- 0.46 mm. 
THE SUCCEEDING LARVAL STAGES. 4 
There are in all five larval stages. The principal” % q 
Rear ye str difference between them is the increase in size after ‘| 
‘eae -each molt, the full-grown larva measuring from 5 to. E 
Pa bal we 5.5 mm. in length 
““pallidula): Egg. There is some variation in the position of the ap- 
Greatly enlarged. pendages along the sides of the body in the various — 
Se stages. After the first molt the head and legs are = 
smaller in comparison with the growth of the body and are not so 
conspicuously out of proportion as in the first instar. The color 
of the body in the second and in the succeeding stages is ight green, 
sometimes tinged with yellow. The cast larval skins of the various 
stages.are often retained on the fecifork up to the time the larva is 
ready to transform to the pupa. They are arranged consecutively, 
that of the first nymphal stage nearest the tip of the fork and with the ~ 
head molts on the upper surface of the pack as it is held over the 
dorsal surface of the body.. 4 
The width of the heads of individuals in any one stage is quite 
constant, that of the second instar being about 0.55 mm., that of the — 
third about 0.67 mm., that of the fourth about 0.82 mm. a that of 
the fifth about 0.97 mm. 
THE PUPA. 
The fringe of appendages persists in the pupa, there being five 
branched’ pairs on the sides of the abdomen and about 45 small 
appendages around the edge of the prominent thoracic shield. The 
