114 Bulletin Vanderbilt Marine Museum, Vol. VI 



the orbit two subequal, more widely separated, fixed, acuminate, 

 subequal teeth, the anterior of which projects the tip a little be- 

 yond the orbit; the rostrum curves downward abruptly just be- 

 yond this spine, and anterior to the eye, runs forward for a short 

 distance, bearing one small spine, which is about one and a half 

 times as far from the preceding spine as the latter is from its pre- 

 decessor ; thence the rostrum curves decidedly upward, the distal 

 two-fifths being obliquely much higher than the highest prerostral 

 crest of the carapace. Beyond this small spine (third of the fixed 

 series, or eighth of the entire series) there are five more similar 

 spines, the proximal four of which are also widely separated from 

 each other and approximately subequal ; the fifth spine is similar 

 to the preceding one, subapical in position, being midway be- 

 tween its predecessor and the acute apex. The inferior rostral 

 margin is armed with thirteen small, acute teeth, the proximal 

 of which is just anterior to the distal margin of the eye, the distal 

 tooth being opposite the third from apex tooth of the superior 

 margin. The postorbital tooth is acuminate; the anterolateral 

 angle is blunted. The abdominal segments are compact, the pos- 

 terior margin of the third segment being moderately produced 

 in the median dorsal region but not dentate ; the sixth segment is 

 five-sixths as long as the telson and has the posterior margin pro- 

 duced on either side in the median lateral area into an acute tri- 

 angle that projects above the telson. The telson is somewhat 

 rounded dorsally, decidedly tapered posteriorly, the distal mar- 

 gin very narrowed and ciliated. There are three pairs of articu- 

 lated, submedian spines on the dorsal surface. The uropoda are 

 well developed. 



The eye is large, bulbous, hemispherical, set upon a short, 

 obconic stalk. 



The antennulae have the basal article elongate-laminate, con- 

 cave beneath the eye, distally curved upward in advance of the 

 eye and fringed with bristly setae ; there is also an outer lateral 

 process to this first article ; the second and third articles are cylin- 

 drical, successively shorter ; the flagella are respectively one and 

 four-tenths and one and eight-tenths times as long as the rostrum 

 and both are exceedingly fine on the distal halves. 



The antennae have the basicerite short, strong, with sinuate 

 distal margin; the second and third articles short, cylindrical, 

 the third article extending as far as the second peduncular article 



