86 PROCEEDINGS OF THE NATIONAL MUSEUM VOL. 118 
Family Euryuridae 
Genus Seminellogon Chamberlin 
Seminellogon Chamberlin, Pan-Pacific Ent., vol. 9, p. 18, figs. 6-8, p. 13, 1923. 
Sigmogonotropis Hoffman, Proc. U.S. Nat. Mus., vol. 102, p. 240, fig. 84, 1951. 
Seminellogon panamicus (Chamberlin), new combination 
Aphelidesmus panamicus Chamberlin, Proc. Biol. Soc. Washington, vol. 38, p. 41, 
1925. 
Canal Zone, male, Gorgona, February 10, 1911, Wiliam R. Maxon; 
2 females, Monte Lirio, June 8, 1923, O. F. Cook and R. D. Martin; 
male and female, Barro Colorado Island, August 2, 1955, C. W. 
Rettenmeyer; male, 2 females, Barro Colorado Island, March 1956, 
C. W. and M. E. Rettenmeyer; female, Pifia area, March 18, 1958, 
H. F. Loomis. 
Panama, male, female, and young, Cerro Campana, March 16, 
1958, E. M. and H. F. Loomis. 
This species was founded on a single female, and no males have been 
reported. Not only do the above males allow placement of the species 
in the correct genus but they also indicate the generic similarity of 
Sigmogonotropis to Seminellogon, a similarity which R. L. Hoffman 
has also seen after examining one of the above males. 
Comparison of above specimens with the description of Szgmogono- 
tropis serratus Hoffman also shows great similarity of the two species; 
the serrations on the side of the larger branch of the gonopods of 
S. serratus are the only major structural difference between them, 
since the gonopods of S. panamicus lack serrations. Further col- 
lections between the respective ranges of the species are likely to show 
that only a single species is involved. 
Family Oniscodesmidae 
Genus Oncodesmoides Kraus 
Oncodesmoides Kraus, Senckenberg Biol., bd. 35, p. 41, 1954. 
The milliped that has been reported from Panama as Oncodesmus 
granosus (Gervais and Goudot), or any of its synonyms, probably 
is one of the most common species in the region of the Canal Zone 
but appears to have been wrongly identified and in reality is a new 
species of the genus Oncodesmoides, which contains two Peruvian 
species. 
