HAWAIIAN ACANTHURID CALIGOIDS— LEWIS 189 



of lateral regions, concealing part of fourth thoracic leg-bearing seg- 

 ment. Longitudinal cephalothoracic grooves distinct, cross groove 

 absent, extending from posterior margin of cephalothorax, just lateral 

 to openings of posterior sinuses, anterior and lateral to just behind 

 eyes. Lateral strengthening regions visible as bar-shaped processes 

 extending from midlateral region of cephalothorax laterally and 

 posteriorly, terminating just medial to lateral margin of cephalothorax. 

 Two distinct grooves extending from anterior margin of cephalothorax 

 posteriorly and medially to region of eyes. Eyes distinct, placed in 

 anterior fourth of cephalothorax, inner margins contiguous on median 

 longitudinal axis of body; median eye remnant visible, contiguous 

 with posterior margins of paired eyes (fig. 13a). 



Fourth thoracic leg-bearing segment short but distinct, drawn out 

 laterally, at junction of fourth thoracic legs. Division between foiu-th 

 thoracic leg-bearing segment and genital segment distinct. 



Genital segment of female concave at junction of fourth thoracic 

 leg-bearing segment, broadly rounded laterally, posterior lateral 

 surfaces forming two large lobes. Fifth legs appearing dorsally as 

 three plumose setae, ventrally as lappet with three plumose setae, 

 two lateral setae of equal length but shorter than single seta just 

 medial to first two (fig. 13c). 



Abdomen rudimentary, fused with posterior sm'face of genital 

 segment, with indistinct, discontinuous line of segmentation visible 

 in stained specimens (fig. 13c). 



Cephalothorax of male similar to that of female except groove 

 between frontal region and cephalothorax somewhat irregular (fig. 

 136). Genital segment width not as great, comparatively, as in female, 

 without posterior lateral lobes as in female. Both fifth and sixth 

 legs visible, fifth legs as two plumose setae on posterior lateral margin 

 of genital segment and one plumose seta slightly anterior to first two; 

 sixth legs as small, projecting lobe with two distal, plumose setae 

 (fig. 13c?). Abdomen broad, short, length less than that of female, 

 division between abdomen and genital segment distinct (fig. 13f/). 



Antennule of female two-segmented, attached to ventral sm*face of 

 cephalothorax just posterior to lateral frontal region margin; not 

 attached to frontal region. First segment about 1.7 times length of 

 second, widest in middle of segment, anterior margin tapered on both 

 sides of widest point. Anterior surface of first segment with 18 

 plumose setae. Second segment club-shaped, with one naked seta 

 from middle of posterior margin, 13 from distal sm'face (fig. 13c). 



Antennule of male similar to that of female except second segment 

 slightly longer; with two naked setae on posterior margin instead of 

 one as in female, one naked seta arising from middle of posterior 

 margin, second from proximal region of margin (fig. 13/). 



