10 PROCEEDINGS OF THE NATIONAL MUSEUM VOL. 125 
3. Part of the surface of the labrum has a “fuzzy” appearance due 
to numerous, minute projections. Shino figures the labrum without 
the projections. 
4. Shino states (p. 415) that, in the first thoracic leg, “both the 
rami (are) fringed by stout long spines with multiserial barbs; . . .” 
This condition was not evident in the Eniwetok material. 
5. The antennae of the Eniwetok specimens possess 2 denticulated 
subterminal setae on the third segment while Shiino indicates that 
there is only 1. 
In spite of these differences, the Eniwetok specimens agree closely 
with Shiino’s original description and, based on this similarity, are 
believed to be conspecific with N. gibber. 
Pseudotaeniacanthus species 
Ficures 5, 6 
MatTeriAL.—1 adult male (USNM 120740) from the external 
surface of Acanthurus gahhm (Forskal). 
MEASUREMENTS (in mm).—1 male: 
Greatest length, excluding caudal setae 1. 73 
Length of prosome 0. 81 
Width of prosome 0. 63 
Length of cephalothorax 0. 49 
Length of genital segment 0. 18 
Width of genital segment 0. 27 
Derscription.—Body (fig. 5a) of general cyclopoid shape: cephalo- 
thorax of general bell shape, consisting of cephalon, maxilliped- 
bearing and first pedigerous segments. Anterior end of cephalothorax 
rounded although slightly concave medially, set off from rest of 
cephalothorax by lateral indentation and line of heavy sclerotization 
extending medially and curving posteriorly from lateral indentation. 
Lateral margins flatly convex, posterior margin irregularly concave. 
Second pedigerous segment distinct from cephalothorax, width 
approximately nine-tenths that of cephalothorax; lateral surfaces 
winglike, lateral margins flatly convex. Third pedigerous segment 
distinct from second, appearing slightly narrower than second although 
of similar shape. Fourth pedigerous segment distinct from third, 
approximately three-fourths its length, lateral surfaces winglike, as 
in preceding free pedigerous segments, although lateral margins more 
rounded. 
Fifth pedigerous segment without winglike lateral projections, 
forming first segment of urosome; slightly narrower anteriorly than 
posteriorly. Genital segment (fig. 56) barrel-shaped, slightly more 
than one and one-half times the length of fifth pedigerous segment; 
