120 
required; whiist for the Cottony Cushion Seale (Plate IJ., Fig. 7), in which the 
‘dimensions of the larvwe are exceptionally large, 24 may be contained in 
‘this measurement. This free life manifested by the scale insect at a period 
.of its existence when it is still very small is the explanation of its apparent 
spontaneous occurrence or increase upon plants whereon its presence had 
- previously escapee observation. Persistent activity throughout life is not, on 
the other hand, a character exclusively possessed by Mealy Bugs; for up 
_to the period of life when the adult female insect is distended with either eggs 
or young, the Soft Scales (or Lecanidw) manifest a certain degree of locomo- 
tion upon their food plants; and in the case of the Cottony Cushion Scale, @ 
similar movement is displayed till even later in life. This feature is exhibited 
_also by other members of the family. 
One of these larval or young scale insects is represented by Fig. 2, Plate 
-III., that relates to this condition in the Circular Purple Scale Insect (Aspidiotus 
ficus) itself shown on Plate L., Fig. 1. 
From an examination of this it will appear that the insect at this period. 
_of its life is marked by distinct lines of division separating the nine different 
abdominal segments of which it is composed, and, moreover, well equipped 
with organs for locometion, subsistence, &c. It has three pair of well- 
developed four-jointed claw-bearing legs, two antenne or feelers, two eyes, and 
a long hair-like organ issuing from between the fore legs and folded upon 
itself—the characteristic proboscis of these insects. There are also two small 
apertures on each side of the body, one being adjacent to the origin of each of 
the first and second legs respectively. These are the breathing pores or spiracles. 
From the hinder border of the body project two long bristle-like organs. The 
legs, as shown in Fig. 8, Plate 1IL., each terminate in four short tubular 
terminally inflated bristles. These are the so-called tenent hairs, and are of 
considerable assistance in securing adhesion to any body upon which the insect 
may happen to occur or which it may encounter. During this active stage—that 
continues, though no food seems to be partaken of, for three or four days, or lasts 
only as many hours—the young Coccid may crawl several feet from their place 
of origin, not only upon the tree itself whereon they come into existence, but also 
_over the soil, and from this to any plant that may be growing therein. ‘Thus 
also when several plants are packed together they may migrate from a single 
one to all those with which this is associated. They may also be borne short 
distances by the wind, or by moving water upon the surface of which they 
float. ‘They again may become attached to a person’s garments, and so be taken 
from one orchard to another; and the same may be accomplished by the 
bodies of other insects, as well as by the limbs of those and of birds also. The 
following allusion to the latter means of transference in the case of the 
Pernicious Seale may be cited in this connection :— 
The active young lice (write Messrs. L. O. Howard and OC. L. Marlatt) soon crawl upon any 
small winged-insect, particularly if the latter be of a dark colour, and may thus be carried 
considerable distances. They are frequently found crawling upon ants, which are great travellers. 
It is extremely probable that they also crawl upon the feet of birds, and may be transported by 
these carriers for many miles. 
Some interesting observations have been made by Mr. Schwarz upon the transporting of these 
seale-larve by other insects. A little black lady-bird, Pentilia misella, which was very active in 
_ ‘devouring scale-larve, was unfortunately equally efficient in transporting many of these youn lice 
to other parts of the tree or to other trees; in fact, it was difficult to find a single beetle whic did 
not carry on its back at least one larva of the San José Scale, and sometimes three or four were 
found upon a single wing-cover of a beetle. The small black ant, Monomorium minutum, was 
particularly abundant upon pears, attracted by the juices emerging from cracks; and almost every- 
‘one of these insects carried on its back one or more specimens of the young scale insects. Speci- 
mens of the little chrysomelid beetle, Zypophorus canellus, were also found upon the trees. th 
red and black specimens of this beetle occurred, and the interesting observation was made that 
while Aspidiotus larvee crawled freely on the black individuals no specimens were to be found 
upon the red ones. The same peculiarity was found to hold true with the ants. The red ant, 
Formica schaufussi, was abundant upon the pears, but no specimens were found bearing Aspid- 
zotus larvee, while, as just stated, the little black Monomorium was always found carrying them. 
As illustrating this transportation of the scale by birds or insects, the experience at Riverside 
Mad., ante page 25, may be cited; and Professor Smith reports a similar instance in New Jersey, in 
letter of 13th January, 1896.* a 
Ee sed beet den Be Stusecreoeld lite dnl SNE A Ae I AEM RETR eae 
* The San José Scale. Bull. 3, New Series, Div. of Entom. U.S. Depart. of Agr, pp. 49-50. Washington, 1896, 
