1973] 
Ra?mousse — A raneus diadematus 
23 
and live at least four months longer (Reed & Witt, 1972). The 
related differential maturing rates may provide an advantageous 
distribution of spiderlings over a period of time. Together, these 
mechanisms would seem to help a species survive drastic or poten- 
tially destructive changes in environmental conditions. This research 
seeks to explore the male’s role in these phenomena. At what rate is 
he growing, maturing and dying during the female’s life cycle? 
This leads to the question of inbreeding. An observation of the 
maturation rates of spiderlings of the same set was conducted in an 
effort to determine if inbreeding is possible. 
Also, if the rate of growth is a factor in the rate of maturation 
(and spiders of the same set are known to present a considerable 
variation in size even under apparently optimal conditions), (Witt 
et al., 1968), is growth prenatally or genetically determined or a 
function of external factors? 
The effects of an even diet independent of manifest behavior (Witt 
et al . , 1972) and differential force-feeding on various schedules 
(Benforado & Kistler, 1972) have already been studied. What, 
however, would happen to the growth rate of male and female 
spiders if they could choose their food quantity through web-building 
frequency? 
The answers to some of these questions about the growth and 
maturation of male spiders should provide clues about their role in 
the reproductive cycle and, more generally, about their role in the 
continuity of the species. 
METHODS 
Two Araneus diadematus cocoons collected in the field, were placed 
in two different rearing boxes in the laboratory, where they hatched 
(February 23, 1972, one cocoon and 14 days later, March 6, 1972, 
the other). The offspring from the first cocoon will be called set I, 
and the offspring from the second cocoon, set II. The laboratory 
provided a cycle of long warm days and short cool nights throughout 
the lifespan of the animals. 
As the animals left the communal web to build individual webs, 
they were put in glass tubes. Five weeks after hatching for set I and 
three weeks after hatching for set II the spiderlings were caged in 
individual labeled frames (50 X 50 X 10 cm) where they could 
build webs without apparent limitation in size. All observations 
began at this moment; however, some molts were noticed inside the 
cocoon, and the spiderlings molted one or two times in the glass tubes. 
