140 
[June 
Psyche 
Figs. 13-14. Lateral views of midbody segments of cave millipeds. Fig. 13. 
Pseudotremia nodosa. Fig. 14. Zosteractis interminata. 
that of Packard’s species, recently found in the Museum of Compara- 
tive Zoology, has shown that there are at least 45 taxa represented, 
many of them known only from single caves. 
The appearance of the true troglobites is strikingly different from 
that of the other species ; the troglobites are usually almost completely 
without pigment, less than 20 mm long, with depigmented and re- 
duced ocelli (represented in some cases by only the cuticular lenses) 
and strongly knobbed segments (Figs. 10, 13). In a series of in- 
creasingly larger epigean forms, the lateral shoulders of the segments 
become more prominent, but the dorsum is not as knobby (Fig. 11). 
Strenuous efforts should be made to collect males wherever this 
genus is discovered. They are easily separated from the females by 
the prominent sclerotized gonopods on the seventh segment. 
Family Tingupidae Loomis 
Epigean members of this family are known from California, Utah, 
and Arizona. 
