1975 ] Eisner, Wood & Eisner — Hydrogen Cyanide 21 
TABLE 
CYANOGENETIC OUTPUT OF MILLIPEDS 
Species 
Sex and Body Weight 
Cyanogenetic Output 
of individual 
(/rg/individual) 
Apheloria trimaculata 
d (769 mg) 
16 
A. kleinpeteri 
9 (1053 mg) 
27 
Pseudopolydesmus branneri <$ (199 mg) 
32 
Cyanogenesis in polydesmoid millipeds involves simultaneous re- 
lease of hydrogen cyanide and aldehyde from stored cyanohydrin 
(Eisner et al ., 1963). The aldehyde has been shown to be benzalde- 
hyde in several species (Barbetta et al ., 1966; Blum et al., 1973; 
Blum and Woodring, 1962; Casnati et al., 1963; Duffield et al., 
1974; H. E. Eisner et al., 1963; Monteiro, 1961; Weatherston and 
Gardiner, 1973). We made no effort to isolate the aldehyde in the 
three North American species, but found evidence that Astrodesmus 
laxus produces benzaldehyde. Gas-liquid chromatography of a sample 
of secretion from this milliped, obtained by wiping the discharged 
fluid from the gland openings with pieces of filter paper, showed a 
peak of identical retention time to that of authentic benzaldehyde. 
Some polydesmoid millipeds have ancillary phenolic components in 
their secretion (Blum et al., 1973; Duffield et al., 1974; Monteiro, 
1961). We did not attempt to isolate such components in our spe- 
cies, although the secretion of Pseudopolydesmus branneri had a phe- 
nolic odor. 
This study was supported by grants AI-02908 and BMS-74-15084 
from the National Institutes of Health and the National Science 
Foundation respectively. We thank Dr. William T. Keeton, Cornell 
University, for supplying and identifying the North American milli- 
peds, and Dr. C. A. W. Jeekel, Zoologisch Museum, Amsterdam, 
for identifying the African species. 
Literature Cited 
Altman, P. L. and D. S. Dittmer. 
1973. Biology Data Book, 2nd ed., vol. II (section 80, part I). Fed. 
Amer. Soc. Exp. Biol., Bethesda, Maryland. 
Barbetta, M., G. Casnati, and M. Pavan. 
1966. Sulla presenze di D- ( + ) -mandelonitrile nella secrezione difensiva 
del miriapode Gomphodesmus pavani Dem. Mem. Soc. Entomol. 
Ital. 45: 169-176. 
