144 Journal of Entomology and Zoology 
Latrodectus mactans Fabricus. Plate V 
Of the family Theridiia, Latrodectus mactans was studied. The 
color of the adult female is coal black, often having a broken row 
of red spots down the median line of the abdomen; the female is 
black with four red stripes on the abdomen besides the broken red 
line down the median line of the abdomen. The female is often 
lacking the red color and then is pure black. The young are a 
light yellow gray white upon emerging, but in thirteen days after 
their first moult outside of the egg case the cephalothorax was 
bright yellow brown with darker brown sides and a triangular 
brown spot in the median area of the cephalothorax reaches to 
the eye space. The abdomen was white with four varying sized black 
spots on its surface. The coxa and trochanter of the legs were yel- 
low brown with dark gray on the upper margin of each; the femur, 
tibia, metatarsus and tarsus were light brown gray with dark gray 
on both upper and lower margins of each joint. The palpi were 
marked the same as the legs, but with a great amount of dark 
gray color. The next moult occurred when the spiderlings were 
twenty days old. The thoracic portion of the cephalothorax was 
dark brown, the sides had a dark gray band and the lower margin 
of this part of the cephalothorax had two dark gray spots. The 
pattern on the median portion of the cephalothorax was more slen- 
der and very black brown. The eye space was light brown. The 
abdomen was a dirty gray ground color. The black spots on the 
one described before had enlarged and between these rows of spots 
were two more broken lines of black spots. The pure white color 
remained only near the margins of the abdomen and as a median 
stripe. The legs were dark brown with darker black brown on the 
upper margin of each joint except the coxa. The palpi were light 
brown having lost all their gray color. At thirty-four days of age 
the cephalothorax had grown lighter, the margins were black with 
a brown stripe bordering the very thin black one. The triangular 
brown pattern on the median area had spread from the eye space 
to the lower margin of the cephalothorax. The abdomen had the 
dirty gray ground color except for the pure white median stripe. 
The abdomen had now three horizontal small black broken lines 
and four large black spots and two broken black lines bordering 
