60 Bulletin Vanderbilt Marine Museum, Vol. VI 



beneath pilosity, situated at the proximal end of the median chan- 

 nel which lies between the large paired, triangular teeth, with 

 apices uptilted, which are well separated by a deep, V-shaped sinus. 



The basal antennal joint is visible dorsally as a small, nearly 

 right-angled triangle, adjacent on either side to the rostral pro- 

 cess ; with the anterior angle of this joint a blunt tooth and an- 

 other blunt tubercle conspicuous midway on the oblique frontal 

 margin; the second antennal joint is expanded, with four acute 

 teeth successively decreasing in size from distal to proximal along 

 the anterolateral margin, the distal tooth being very long, acute, 

 with a pronounced median dorsal carina; the second, third and 

 fourth teeth each have an acute, procurved, horny tip ; the third 

 antennal article is also laminate with two acute teeth on the 

 proximal part of the inner lateral margin, these teeth being semi- 

 erect and procurved, the proximal tooth the smaller one and em- 

 phasized by a large blunt tubercle inside of it on the dorsal surface 

 in line with that on the margin of the first article ; there are eight 

 triangulate teeth along the distal margin of this article, the outer 

 three or four of these frequently being concealed beneath the great 

 tooth of the second article. The dorsal surface of the antennae are 

 pilose, especially along the margins of the joints and the distal 

 margin between the teeth. The antennae are well separated 

 throughout their length by a distance equal to the width of the ros- 

 tral process. 



The antennulae arise beneath the rostral process, the thick, 

 pilose, cylindrical, basal joint extending as far as the base of the 

 third antennal article; the second antennular joint is much slen- 

 derer, cylindrical but stout, one and one-fourth times as long as 

 the first article ; the third article is similar but slightly slenderer, 

 only three-fourths as long as the second; the flagellum is rudi- 

 mentary, consisting of two thick branches, the outer, larger one 

 being one-half as long as the third article and setose ; the inner 

 branch is three-fourths as long as the outer branch ; both are thick 

 for the proximal two-thirds of their length and compressed lat- 

 erally, the respective distal thirds being abruptly slenderer; the 

 inner branch has a brush of setae on its inferior surface. 



The eye is set out on the extreme anterolateral angle, which 

 is excavate on the inferior surface by a deep semioval and on the 

 upper surface of carapace has the exposed semihooded excavation 

 previously described ; the stalk is slender, cylindrical, calcareous ; 



