Pomona College, Claremont, California 143 
A great number of juveniles of the species Misumessus asperatus 
were collected and only the approximate ages can be stated in the 
following discussion of them. The adult female is described as 
“pale yellow in color with dull red markings or the ground color 
may be greenish. There is a brownish stripe on each side of the 
thorax, a median light red band on the basal half of the abdomen, 
two bands or rows of spots on the hind half and a band on each 
side. The male resembles the female in colors and markings, but 
is only about one-half as long.’”” The newly-emerged are light yel- 
low in color of abdomen, cephalothorax and legs, with slight red- 
dish markings on the sides of the cephalothorax and the dorsal 
portion of the abdomen. At the age of three months the males 
could be separated from the females although the palpi showed 
no differentiation, but the size of the two were quite distinct. The 
male at this age has the bright yellow cephalothorax with a brown 
band on either side of the median space. This band does not go 
to the side of the cephalothorax but extends around the anterior 
and posterior lateral eyes. The abdomen is marked the same as 
the adult, only not so distinctly. The coxa, trochanter and femur 
of the legs and palpi are light yellow brown with an indistinct red- 
dish band at the upper margin of each joint. The tibia, tarsus and 
metatarsus are light yellow. In the adult male, the coxa is yellow 
brown, the trochanter and femur are the same with a small red 
band at the upper margin of each joint and the upper half of the 
tibia, the metatarsus and tarsus are dark red. The trochanter is 
covered with small dark red spots. The spines of the juvenile 
male had developed at the age of three months to the size of the 
adult spines. In the matter of size, the juvenile was about three- 
fourths the size of the adult. The juvenile female of the same 
age was marked like the adult, only fainter, and the size was about 
the same proportion as in the other sex. 
In following through a life history of Philodromus pernix, 
NXysticus Californicus and Misumena aleatoria it is found that the 
color changes that take place from the newly-emerged to the adult 
indicate the pattern of the adult. The colors may not be as distinct 
as on the adult, yet on each succeeding moult the pattern becomes 
plainer. Thus it can be said that the Thomiside change very little 
from the immature to the mature in the case of color and pattern. 
