128 BULLETIN 15 8, UNITED STATES NATIONAL MUSEUM 



often completely fused, except for the marginal sinuses, as shown 

 in the figure, thus appearing 3-segmented. Total length, 1.5-2 mm. 



Male. — Luminous organ and the widened and flattened fifth leg on 

 the right side; endopod of right second leg invaginated, of left leg 

 not invaginated; grasping antenna on the left side; basal segments 

 of first antennae with small teeth only on the anterior margin, no 

 large ones; spiniform process on third segment of right fifth leg 

 denticulate distally; left leg apparently 4-segmented and about the 

 same length as the right leg. Total length, 1.5-1.85 mm. 



ReTnarks. — The symmetrical urosome, the form and armature of 

 the fifth legs, and the fact that the second endopod on the left side in 

 the male is not invaginated form the distinctive characters. 



Family LUCICUTIIDAE 

 Genus LUCICUTIA Giesbrecht, 1898 



Head separated from first segment; fourth and fifth segments 

 fused wdth rounded corners; urosome 4-segmented in female, 5-seg- 

 mented in male, symmetrical; exopod of second antenna 8-segmented; 

 rami of first four pairs of legs 3-segmented; fifth legs biramose in 

 both sexes, in the female exopods 3-segmented, endopods 2- or 3-seg- 

 mented, in the male rami of right leg 2-segmented, of left leg 

 3-segmented. 



KEjy TO THE SPEX^IES (BOTH SESES) 



1. Total length more than 5 mm. ; genital segment a little asym- 

 metrical grandis (p. 128) 



Total length less than 3 mm. ; genital segment symmetrical curta (p. 129) 



Total length between 3 mm. and 5 mm. ; first antennae reaching 

 at least 2 segments beyond caudal rami magna (p. 130) 



LUCICUTIA GRANDIS (Giesbrecht) 

 FlQTIRB 86 



Leuckartia grandis Giesbrecht, Bull. Mus. Comp. Zool., vol. 25, no. 12, p. 258, 



pi. 4, fig. 4, 1895. 

 Lucicutia grandis van Breemen, Nordisches Plankton, Zoologischer Teil, vol. 4, 



Entomostraca, Copepoda, p. 114, fig. 131, a^c, 1908. 



Occurrence. — One female from trawl wings, Station 1029, Fish 

 Hawk., southeast of Nantucket; five males and females from trawl 

 wings. Stations 2195, 2219, 2224, Albatross., south of Marthas Vine- 

 yard; two males in vertical haul, Station 20069, Gramyus. 



Dist'rihution. — Atlantic, north of British Isles (Wolfenden) ; 

 Pacific, off Ecuador (Giesbrecht); Gulf of Maine (Bigelow). 



Color. — Body transparent and colorless, except that some of the 

 setae and spines on the mouth parts and the swimming legs are dark 

 reddish brown ; eye red. 



