Genus Scytonotus 
11 
cylindrical shape to this part of the body. The paranota are vesti- 
gial on segments 5 and 9 and are absent from segments 6-8. The 
distinction applies only to adults; I have examined innumerable ju- 
venile females of different sizes, and presumably different instars, 
with well developed paranota on these segments. Loss of these structures 
thus appears to occur at the final molt and to coincide with the 
attainment of sexual maturity. 
Male gonopods — As in all polydesmids, the most important 
taxonomic features in Scytonotus are located on the gonopodal telopo- 
dite, which consists of two branches that join basally. I adopt the 
system of Attems (1940) and Golovatch (1991) and label the blade- 
like, anterior projection as the “tibiotarsus” and the variable caudal 
structure with a pulvillus on the inner margin as the “endomerite.” 
Three laminae arise from the endomerite stem, one each on the 
medial and lateral sides and one distad. The principal taxonomic 
characters involve the relative lengths of the tibiotarsi and the endo- 
merites as well as the sizes and configurations of the three lamelae. 
Medial lamina — The medial lamina arrises proximally on the 
endomerite, often proximal to the pulvillus, extends for varying lengths 
along the stem, and usually terminates before the modifications of 
the distal lamina. In most species the medial lamina expands ba- 
sally into a variable lobe or flange that may overhang and partly 
obscure the inner margin of the endomerite. Distally it varies greatly, 
tapering smoothly onto the endomerite in S. piger, columbianus, 
inornatus, and granulatus (Figs. 5, 7, 17, 21), and terminating in 
one or more variable teeth or spurs in S. insulanus, bergrothi, sim- 
plex , virginicus, and australis (Figs. 11, 13, 15, 23, 25, 27). 
Distal lamina — The distalmost part of the endomerite, the dis- 
tal lamina arises at varying points along the stem beginning near 
midlength. There are three basic configurations: with two or three 
teeth on the inner margin, as in S. piger , columbianus, granulatus, 
virginicus, and australis (Figs. 5-8, 21-28); expanded basally into a 
small lobe or spur and prolonged distad to varying degrees, thus 
extending beyond the distal extremity of the tibiotarsus, as in S. 
insulanus, bergrothi, and simplex (Figs. 11-16); and unmodified, as 
in S. inornatus (Figs. 17-18). 
Lateral lamina — Like its medial counterpart, the lateral lamina 
arises at various points along the endomerite stem, in some species 
proximal to the pulvillus, and usually terminates proximal to the 
modifications of the distal lamella. The structure is long, slender, 
and unmodified in S. piger, columbianus, inornatus, and australis 
(Figs. 6, 8, 18, 28); expands into rounded lobes in S. insulanus 
and bergrothi (Figs. 12, 14); possesses a subspiniform projection in 
