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Psyche 
[June 
Genus Speodesmus Loomis 
Fig. 4 
Causey (1959a) has already noted the remarkable loose-jointed 
appearance of the members of this genus, due to the elongated legs 
and body segments. They are undoubtedly troglobites. The two 
known species can only be separated by reference to the male gono- 
pods. Both are found in caves of the Edwards Plateau of Texas. 
Speodesmus echinourus Loomis (Fig. 4) is known from caves in 
Kerr and Hays Counties (Loomis, 1939; Causey, 1959a); S. bi- 
cornourus Causey from Beck’s Ranch Cave, Williamson Co. (Causey, 
J 959a). Both species are considerably larger than the preceding 
genus, being 12-20 mm long, and they have much more prominent 
paranota, the posterior angles of which are drawn out posteriad. 
Genus Speorthus Chamberlin 
The single species of this genus, S. tuganbius Chamberlin, was 
described incompletely and without illustration (Chamberlin, 1952), 
but Loomis (i960) subsequently located and illustrated the male 
holotype. Although tuganbius is only 8 mm long, the gonopods look 
very much like those of Speodesmus , and it is quite likely that this 
name is a synonym of Speodesmus. It is known only from the types, 
collected in 1924 in Carlsbad Caverns, New Mexico. 
Genus Tidesmus Chamberlin 
It is clear from the description given by Chamberlin (1943) of 
the type species, T. epis copus, an epigean species, that Tidesmus 
hubbsi , described in the same paper, is not a member of that genus, 
and perhaps not even a member of the same family. The illustrations 
of the gonopods of episcopus are quite similar to those of members 
of the genus Phreatodesmus (Loomis, i960). Thus Tidesmus , the 
older name, may eventually become the proper name of the species 
now grouped under Phreatodesmus. Only a study of the type ma- 
terial, now unavailable, will solve this kind of problem, common in 
diplopod taxonomy. But for the present, I will only note that Tides- 
mus hubbsi was described from the cave of Cave Valley, Lincoln Co., 
Nevada. 
Family Nearctodesmidae Chamberlin and Hoffman 
Genus Ectopodesmus Hoffman 
The single species of this genus, E. remingtoni Hoffman, was orig- 
inally described from an unnamed cave 1.7 miles north of Grafton, 
