246 U.S. NATIONAL MUSEUM BULLETIN 236 



and Parametis Labbe, 1926. The type species is Metis ignea Philippi, 

 1843. The following species and subspecies are now recognized: 



Females Males 



Metis ignea Philippi, 1843 M. ignea Philippi, 1843 



{= Ilyojisyllus coriaceus Brady and Robertson, 1873; Thoraco- 



sphaera injlata Kriczagin, 1873; Carazzoides venetus Grandori, 1912; 



Riibeus venetus Grandori, 1912; Parametis sangineus Labb6, 1926) 

 M. i. halmyricola Marcus and P6r, 



1961 

 Abacola holothuriae Edwards, 1891 A. holothuriae Edwards, 1891 



(= Ilyopsyllus jousseaumei Richard, 1892; /. affinis T. Scott, 



1894; /. Sarsi Sharpe, 1910) 

 /. natans Williams, 1907 /. natans Williams, 1907 



M. pallida Gurney, 1927 



A single male specimen of Metis holothuriae occm's in the collection. 



Metis holothuriae (Edwards, 1891) 



FiGUEEs 98, 99 



Abacola holothuriae Edwards, 1891, p. 92, pi. 5 (figs. 1-17). 



Metis jousseaumei f. minor Sewell, 1940, p. 346, fig. 86. — Krishnaswamy, 1953, 



p. 75. 

 Metis jousseaumei f. major Sewell, 1940, p. 349, figs. 87, 88. — Krishnaswamy, 



1953, p. 75. 

 Metis jousseaumei.— 'Nicholls, 1941, p. 425; 1941a, pp. 317-328, figs. 1-5; 1942a, 



p. 138; 1944a, p. 502; 1945, p. 14.— Carvalho, 1952, p. 164, pi. 2 (figs. 89-91). 

 Metis holothuriae. — Lang, 1948, p. 777, fig. 315 (no. 2) — Noodt, 1955a, p. 207. 



Material. — Loc. 592, 1 ad. cf, 0.51 mm. 



Description. — The following is based on the only male specimen 

 available, which has been dissected and mounted. 



Adult male, total length 0.51 mm.; greatest diameter 0.19 mm.; 

 length of longest furcal seta 0.42 mm. 



Shape of body highly characteristic: strongly inflated cephalo tho- 

 rax, principally composed of very big cephalic somite, resulting from 

 fusion of head and 1st thoracic somite. The remaining 4 thoracic 

 somites are short and in this contracted specimen almost completely 

 concealed under the distal border of the cephalic somite (fig. 986). 

 Abdomen short, not more than ji length of cephalic somite. Back 

 strongly curved, vaulted, curving into short, strong, downwardly 

 directed rostrum, apex of which is rounded and hidden between basal 

 parts of antennules (fig. 98a). Sides of cephalic somite produced to 

 shield basal parts of oral appendages. Thoracic somites 2 to 5 narrow, 

 with rounded, scarcely produced epimeral plates, backwardly drawn 

 out in rounded flap. 5th thoracic somite with distal fringe of spinules. 



Abdomen composed of 5 somites, somites 1 and 2 separated. All 

 abdominal somites, including the anal somite, have about the same 



