1980] Tietjen — Sanitary Behavior of Mallos gregalis 
63 
Following data collection, the information saved on tape was loaded 
back into the CDP-1802 computer and formated for analysis. 
Although the CDP-1802 computer is well suited as an intelligent 
controller, it is laborious to program statistical analyses in such a 
system. For this reason, the formated data were transmitted to 
another computer for numerical analyses (Ohio Scientific C1P). 
Statistical analyses were performed according to the methods of 
Conover (1971) and Sokal and Rohlf (1969). All means are accompa¬ 
nied by their standard deviations. 
Results 
The distribution of silk in all colonies was clumped with variance to 
mean ratios ranging from 79.4 to 126.0 (Chi-Square test p<.001; 
Table 1). Examination of the data indicated that nearly all of the silk 
was deposited near the periphery of the container with little or no silk 
deposited in the central area (Fig. 2, 3). The edge of the petri dishes 
contained numerous chambers and tunnels common to typical M. 
gregalis webs (Burgess, 1976). Most silk appeared to be dragline 
rather than cribellate silk. 
Table 1 
Intermediate results for the number of animals, silk density and number of excreta 
for colonies of Mallos gregalis reared in containers of two sizes. The variance to mean 
ratios indicate considerable clumping of silk within all colonies (Chi-square test, 
pC.OOl). Silk density is expressed in arbitrary units related to the amount of light 
received by the camera. 
Number of 
Number of 
Mean Silk 
Variance to 
Mean Ratio 
Number of 
Excreta per 
Size 
Animals 
Pixels 
Density 
for Silk 
Colony 
small 
5 
511 
257.1+148 
85.2 
16 
5 
487 
226.5+140 
86.5 
10 
5 
510 
272.7+198 
88.6 
13 
20 
503 
312.1+198 
126.0 
43 
20 
500 
363.3+170 
79.4 
34 
large 
5 
582 
255.9+151 
89.2 
12 
5 
588 
273.6+154 
86.6 
30 
10 
555 
265.2+148 
82.4 
27 
10 
576 
284.1+161 
91.8 
31 
20 
554 
322.6+194 
116.9 
30 
