50 THE SAX JOSE OR CHINESE SCALE. 
of May; at Amherst, Mass., they were first noticed June 12, and in 
Arizona they are recorded as appearing in March. The larvae are con- 
tinuously present on the trees until further hatching is prevented by 
severe frosts. In 1894, as we have already shown on page 289 of Vol- 
ume VII of Insect Life, the first frosts at Washington occurred in the 
latter part of October and the hatching of the young ceased before the 
1st of November. October 24, 1894, however. Doctor Howard saw 
recently settled larvae, not more than 5 days old, at Lewisburg, Pa. In 
L895 the October frosts were insignificant, and in this neighborhood 
no severe frost occurred until about the 1st of December. The result 
was that young larvae were found at Washington until late in Novem- 
ber, while on twigs received from Chestertown, Md., November 13 and 
November '21. the young were more or les^ abundant. The cold spell 
of the last week in November and the first week in December put a 
stop to development here. This same cold spell was of very wide 
extent. As far to the southwest as San Antonio. Tex., the thermom- 
eter dropped to 31 c on December 3. A similar, or even lower, tem- 
perature was noted at New Orleans, yet on December 16 Doctor 
Howard found newly hatched young, les^ than 24 hours old. upon a 
plum tree at Audubon Park. New Orleans. 
In autumn, or when further development is stopt by cold weather, 
hibernation is begun by scales in all stages of development, from the 
white, minute, down-covered recently hatched young to the mature and 
full-grown females and males. Unquestionably many young perish 
during the winter, and normally in spring quite a percentage of the 
smaller or half-grown scales will be found to have perished. It is 
very probable that many females have union with the males in the fall. 
but the majority of them are unquestionably immature, and are fertil- 
ized in this latitude early in April by overwintered males which, as we 
have noted, appear nearly a month before the first young of the spring 
brood. 
The actual rate of the production of young at different periods of 
the life of the adult female has not been determined with accuracy. 
As the average reproducing period of the adult female i^ six weeks, 
and as the average number of young from each female is about 400, 
there must be born from !» to 10 young every twenty-four hours. The 
great labor of watching an individual female and removing every 
twenty-four hours the young she has given birth to during that period 
has not been entered upon. Sufficient observations have been made, 
however, to indicate 4 that the main period of reproductive activity is 
the second or third week after tla^ female has reached maturity. At 
first the young are born with less frequency, and there i- a correspond- 
ing reduction in reproductive activity toward the end iA' the life o\' the 
individual. The young are born indifferently by day or by night, per- 
haps more during the day than during the night. In the morning. 
