PSYCHE 
VOL. 53 
March- June, 1946 
Nos. 1-2 
PARTURITION IN PERIPATUS 
By Peter R. Morrison 
Biological Laboratories, Harvard University, 
Cambridge, Massachusetts 
Despite numerous and extensive studies on the habits and life 
history of various of the Onychophora, 1-5 with the exception of 
Steel 4 who reported no details, there appear to have been no 
observations on parturition in this group. This is perhaps not 
surprising when one considers their retiring nature and strong 
negatively phototropic reactions which make difficult even the 
observation of the more ordinary activities such as ecdysis and 
feeding. Since their viviparous mode of reproduction is one of 
their more unusual characteristics, observations on parturition 
are of interest. 
These peripatus were secured on Barro Colorado Island, 
C. Z., through the great kindness of Mr. James Zetek. They 
were taken in September of 1941 and these observations were 
made in Cambridge about a month later. During the interim 
they were kept in moist forest debris but were not given addi- 
tional suitable food. The large female in which successful par- 
turition was observed had an extended length of 60 mm, had 
33 pairs of legs and was uniformly colored a rich red-brown. 
It was Epiperipatus brasiliensis vagans Brues, 6 for which the 
Island is the type locality. Twenty three days previously she 
had given birth to a single young and another was found just 
before these observations were made. 
1 Manton, S. M., Ann. Mag. Nat. Hist., (11) 1:515-528 (1938). 
2 Holliday, R. A., Ann. Natal Mus., 10:237-244 (1942). 
3 Andrews, E. A., Quart. Rev. Biol., 8:155-163 (1933). 
4 Steel, T., Proc. Linnean Soc. New South Wales, 21:94-104 (1896). 
5 Sedgwick, A., Quart. Jour. Micr. Sci., 28:431-493 (1887). 
6 Brues, C. T., Psyche, 32:159-165 (1925). 
