94 
Psyche 
[March-June 
on June 12 to 17.91 mg ± 2.56 on July 13; there was a significant 
interaction between time and feeding schedule below the 1% level. 
FEEDING AND Maturation: If the number of molts over time is 
taken as an indication of speed of maturation, then a relationship 
between feeding and rate of maturation can be seen. During the 
period of differential feeding the number of molts of the heavy-fed 
and light-fed groups differed significantly at the 5% level. The 
heavy-fed group had a mean number of 3.0 molts while the light-fed 
group had a mean number of 2.3 molts. These results are in agree- 
ment with the findings reported by Deevey (1949) with Latrodec- 
tus mactcins (Fabricius) and indicate that in the laboratory with 
only food quantity as a variable, a relationship exists between the 
rate of weight increase and the rate of maturation. 
INITIAL WEIGHT and rate of growth: From the beginning of 
the experiment we noted a wide variation of weights of the individ- 
ual animals. At the onset of differencial feeding individual weights 
ranged from 1.1 mg to 16.2 mg. In both the light-fed and heavy- 
fed groups there existed a positive correlation between initial weight 
and final weight. For the light-fed group r = 0.7713 and for the 
TABLE 1 
Measurement 
Light-fed 
Early Late 
Heavy-fed 
Early Late 
Mean wt. (mg) of spiders 
12.52 
22.30 
20. 1 4 
59-34 
Spiral area (cm 2 ) 
1 18.92 
119.51 
1 19.88 
138.32 
Center area (mm 2 ) 
7 1 1 .00 
877.53 
920.30 
1424.30 
Thread length (m) 
7-35 
7-47 
7.56 
8.47 
Mesh width (mm 2 ) 
20.16 
22.34 
21.79 
27.48 
Angle regularity 
4-25 
4.16 
5.52 
4.62 
# of oversized angles 
Relative deviation of 
1.67 
1.87 
2.50 
1.80 
spiral turns (South) 
0.34 
0-33 
0.41 
0.35 
Selected measurements of webs built by a group of light-fed and heavy-fed 
spiders. Because not all spiders built on the same day, early and late webs 
of both groups were chosen from two five day periods two weeks apart. 
Measurements are divided into those which measure size (above the broken 
line) and those which measure regularity. Note the difference between the 
light-fed and heavy-fed animals in measures of web size at the late date. 
While the heavy-fed group increased in all size measures (see Fig. 2), no 
web regularity measures changed. For an explanation of web measure- 
ments see Witt et al., A Spider’s Web. 
