Boone, Crustacea, Cruises of "Eagle" and ''Ara," 1921-28 215 



Dr. Pilsbry states that he found great variation in the degree of 

 asymmetry among the specimens from most stations; either the right 

 or the left scutum may be the more convex. Some individuals are 

 nearly symmetrical bilaterally. 



The "Ara" specimens, one of the larger of which is figured, may 

 all be considered representative of the typical form. None approaches 

 the subspecies, hreve Pilsbry. 



Technical description : The capitulum is inequilateral, oblong, the 

 carinal margin very convex, the occludent margin slightly so. The 

 plates have a minute sculpture of fine radial striae and low, moder- 

 ately coarse concentric wrinkles. The occludent border is moderately 

 arcuate, the greatest curvature being near its apex and base. The 

 umbo is incurved and somewhat produced. The basal margin is short, 

 oblique. There is only a vague trace of a curved ridge from the umbo 

 to the junction of the carina and tergum and there are no distinct 

 angle in the outline of the plate at the tergo-carinal suture. There 

 is a distinct ridge extending from the umbo to the apex, nearly 

 straight on the apical half and defining an occludent area. The ter- 

 gum is small and wedge-shaped, but wider than the carina, the carinal 

 end being truncated, or slightly rounded. The tergum is marked by 

 radiating and growth striae. The cornea is very narrow and slender, 

 regularly arcuate, with a narrow, rounded roof. The roof is a little 

 wider above than near the umbo, but the sides are a bit wider below. 



The peduncle is short, with prominent rings. 

 Synonymy. — Poecilasma inaequilaterale Pilsbry, Bull. 60, U. S. Nat. 

 Mus., p. 85, pi. 6, figs. 6, 7, 8, 11, 12, 1907. 



COPEPODA. 



Family: CALANIDAE. 



Subfamily: Pontellinae Dana. 



Genus: PONTELLA (Dana). 



Pontella plumata (Dana). 



Plate 82. 



Discussion : A figure of the female of this exquisite minute animal 

 is given. Brady has described and figured the species in masterly fash- 

 ion in his report on the Copepoda of the ''Challenger*' Expedition. 



The unusually long, dense plumose setae of the antennae and man- 

 dibles of the female are short and scarcely at all plumose in the male, 



