Pomona College, Claremont, California 133 
habitat. The difference in time with all of them was from one to 
two months. This could be accounted for by the fact that they 
were raised in a steam-heated room and were placed in the sun- 
shine from two to three hours a day even in winter, and so devel- 
oped quicker. Artificial help was given to some species which 
seemed to have trouble in emerging. The mother spider in some 
cases cuts the silk of the cocoon and so when some species were 
particularly long in hatching, a pin point was inserted and an open- 
ing made. Without the help of the female Lycosa the young were 
not able to emerge at all. The young would develop in the egg 
sac up to the emerging and then would dry up, if not given arti- 
ficial aid. 
The actions of the newly-emerged young of the different species 
were constant. Lycosa upon emerging clambered upon the body of 
the mother, nearly covering the mother spider. The lycosids which 
were hatched artificially and had no mother to clamber on died 
soon after emerging. The young which emerged and were carried 
by the mother all lived, but the others did not seem to have the 
necessary strength. The mother often seemed anxious to get rid 
of the young. If disturbed she threw them off, and if they were 
too young they died. A female without an egg sac was put with an 
artificially opened sac and soon the young clambered up on the 
legs and abdomen of the adult without any response from her. 
Another female carried her own egg sac and a load of orphans 
which were placed with her. This double load seemed to be too 
much for her; for she died before her own brood could emerge. 
The brood which had lived on her a week while she carried her 
own case, lived. After she died they started an independent life, 
but generally the young live on the mother two weeks after emerg- 
ing. These experiments would seem to show that to some degree 
the life of the young depended upon the existence of the mother. 
None of the other families studied had this dependence of the 
young upon the mother. 
The young of Peucetia built simply a line of thread and stayed 
on it or ran around the jar unattached by any silk. The Thomi- 
side when very small would climb upon the flowers or leaves and 
bark, seemingly waiting for little mites or flies. Latrodectus and 
