HYDROGEN CYANIDE PRODUCTION IN 
NORTH AMERICAN AND AFRICAN 
POLYDESMOID MILLIPEDS 1 
By Hans E. Eisner, 2 William F. Wood, 3 
and Thomas Eisner 2 
A diversity of substances has been isolated from the defensive secre- 
tions of millipeds, including hydrogen cyanide, benzaldehyde, phenols, 
1,4-benzoquinones, quinazolinones, and nitrogen-containing terpenes 
(references in Altman and Dittmer, 1973; Duffield et al., I 974 J 
Meinwald et al., 1975; SmolanofT et al., 1975; Wood, 1 974 ; Wood 
et al., 1975). Hydrogen cyanide, the first of these compounds iden- 
tified (Guldensteeden-Egeling, 1882), has been reported from over a 
dozen European and New World species, all members of the sub- 
order Polydesmida (Barbetta et al., 1966; Blum and Woodring, 
1962 ; Blum et al., 1973 ; Casnati et al., 1963 ; Davenport et al., 1952, 
Duffield et al., 1974; Eisner et al., 1963; H. E. Eisner et al., 1963; 
Hall et al., 1969; Monteiro, 1961). We have demonstrated hy- 
drogen cyanide production in four additional polydesmoid species, 
strengthening the view that cyanogenesis may be of widespread, if 
not general, occurrence within the suborder. Three of the species, 
Apheloria trimaculata, A. kleinpeteri, and Pseudopolydesinus branneri, 
stemmed from the U. S. A. (the first species was from Clifton Forge, 
Virginia; the other two from Roanoke, Virginia) ; the fourth species, 
Astrodesmus laxus, was from Africa (Mombasa, Kenya). The ani- 
mals were tested for cyanogenesis by manipulating them and gently 
squeezing them, while at the same time holding beside their bodies 
strips of filter paper impregnated with benzidine acetate-copper ace- 
tate reagent (Feigl, 1966). In all instances the papers turned blue, 
indicating release of hydrogen cyanide vapor from their glands. In 
single individuals of each of the North American species, cyanogenetic 
output was assayed quantitively (see accompanying table), using the 
technique previously developed in our laboratories (H. E. Eisner 
et al., 1967). 
1 Report No. XLII of the series Defense Mechanisms of Arthropods. 
2 Section of Neurobiology and Behavior, Division of Biological Sciences, 
Cornell University, Ithaca, N. Y. 14853 
international Centre of Insect Physiology and Ecology, P. O. Box 30772, 
Nairobi, Kenya. 
Manuscript received by editor February 25, 1975 
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