146 
PACIFIC SCIENCE, VoL XV, January 1961 
TABLE 3^ 
TABLE 5 
Coluber radiatus, MUTILATION OF THE Tail 
WHOLE 
MUTI- 
LATED 
TOTALS 
Young 
17 
2 
19 
Adult 
42 
12 
54 
Total 
59 
14 
73 
concluded, therefore, that there is no suggestion 
of sexual dimorphism in body length. 
TAIL: For a fighting species the number of 
broken tails does not seem excessively high: 
14 in a total of 73. The figures for both sexes 
are given in Table 3- One might ask whether 
the males show more mutilated tails than do 
the females, or whether it is the other way round, 
or perhaps whether there is no difference at all. 
For the data shown here, x 2 ls very small, 
and the deviation from the hypothesis of in- 
dependency is very probably due to chance. In 
other words, there is no association between 
frequency of mutilation and sex. 
If we should take the young animals of both 
sexes together and, similarly, the older ones of 
both sexes, and divide these into groups of 
mutilated and of nonmutilated individuals, then 
Table 3 a will show these new figures, x 2 
1 . 21 , and it is not. possible to see here an as- 
sociation between the length of life and the 
number of casualties. 
The length of the tail and the body for non- 
mutilated animals is given in Table 4, and the 
illustration in Figure 2. 
In both sexes the relative length of the tail 
TABLE 4 
Coluber radiatus, LENGTH OF Body AND OF TAIL 
AVERAGE LENGTH OF THE: 
N 
Body 
Tail 
Tail 
length in 
°/ 00 of 
body 
length 
Males, juv 
6 
658 
165 
250 
adult 
28 
1155 
288 
252 
Female, juv. 
6 
640 
153 
239 
adult 
13 
1170 
281 
240 
Coluber radiatus, THE LENGTH OF THE TAIL 
in %cc of the Body Length 
N 
R 
Md=<r n 
enter a 
Vdzo-y 
Males 
Females 
28 
13 
230-286 
222-268 
251-3 2.3 
240.0±3.4 
12.3 — 1.6 
12.2±2.4 
4.9 ±0.7 
5.1 ± 1.0 
is the same in both the group of young and that 
of the adult animals. 
Between the sexes there is a difference which 
is small but which may well be real: D/o- d is 
2.76. The hypothesis that there is a sexual 
dimorphism in the length of the tail seems more 
probable than the alternative. 
FERTILITY: Kopstein (1941) reports the ob- 
servation of van Heurn, who saw 8 eggs in one 
nest, and adds an observation of his own upon 
a nest with 10 eggs. Smith (1943) mentions 
from 5 to 12 eggs laid at a time. In our mate- 
rial, four animals carried mature eggs in the 
uterus or in the ovaries. The figures are sum- 
marized in Table 6. 
The average number of eggs per female is 
about 7, with 5 of them on the right side and 
2 on the left. 
TOPOGRAPHY : Data on the topographical pat- 
tern of the organs are available for 27 male 
adult animals with an average body length of 
1196 mm., and for 9 adult females with an 
average body length of 1200 mm. 
In this case it is already apparent from the 
average figures that all of the organs are situated 
more cranially in the female than in the males, 
Tail COLUBER RADIATUS 
t ®„- 
’So+V’' 
400 600 800 10O0 1200 l 400 
B ody length in mm 
FIG. 2. Body lengths as related to tail lengths. 
1 
I 
