316 BULLETIN 15 8, UNITED STATES NATIONAL MUSEUM 



posterior margin of the third thoracic segment; outer margin spines 

 on the three exopod segments of the first leg 1, 1, 3; of the fourth 

 leg 1, 1, 2; of the second and third legs 1, 1, 3. Total length, 0.65- 

 0.75 mm. 



Male. — Unknown. 



Remarks. — As might be inferred from the specific name, the best 

 single character of this species is the reduced length of the first 

 antennae. Another distinguishing mark is the three short outer 

 spines on the end segment of the first exopod. This is evidently 

 another littoral species that is likely to be found in the tidal pools 

 and salt ponds of the area. 



Genus OITHONINA G. O. Sars, 1913 



Body slender, metasome moderately widened, urosome narrow, 

 4-segmented in female, 5-segmented in male; head separated from 

 first segment and squarely truncated anteriorly; rostrum lacking in 

 both sexes; caudal rami no longer than anal segment. First antennae 

 14-segmented, but segments often fused, not reaching beyond the 

 third metasome segment, twice geniculate in male; second antennae 

 3-segmented. Rami of first four pairs, of legs 3-segmented ; outer 

 exopod spine present on middle segment of second and third legs, 

 and on the two basal segments of fourth legs ; fifth leg with a single 

 apical seta and none on the side of the fifth segment. A single 

 species. 



OITHONINA NANA (Giesbrecht) 



Figure 190, c, d 



Olitiona nana Giesbrecht, Fauna und Flora des Golfes von Neapel, vol. 19, p. 



538, pis. 4, 34, 44, 1892. 

 Oithonina nana Sars, Crustacea of Norway, vol. 6, p. 5, 1913. 



Occurrence. — Two females in surface tow in Buzzards Bay, July, 

 1926. 



Distribution. — Bay of Naples (Giesbrecht) ; Red Sea, Arabian 

 Sea, Indian Ocean (Thompson and Scott) ; Pacific coast (Esterly) ; 

 Cape of Good Hope (Cleve) ; Black Sea (Kramer) ; Adriatic (Car, 

 Steuer, Carazzi, Grandori, Pesta) ; Narragansett Bay (Williams). 



Color. — Body not very transparent, irregularly mottled with yel- 

 lowish green, especially in the posterior portion of the urosome and 

 in the maxillipeds. The posterior part of the head usually contains 

 on either side a little brownish-red pigment. Eye carmine-red ; eggs 

 yellowish green with red centers, both colors becoming darker as 

 the eggs develop. 



Female. — Body rather short and stout, metasome widened, fore- 

 head squarely truncated, rostrum entirely lacking, urosome linear; 

 caudal rami as long as the anal segment, twice as long as wide. First 



