190 PROCEEDINGS OF THE NATIONAL MUSEUM. tol. 51. 



c". Dorsal rays II, 10; pectoral rays 20; ventral fossa (before anus) 

 smaller, round ; interorbital wider than eye ; pectoral less than half 



as long as head nipponensis. 



b\ Eye more than two-thirds postorbital length of head; ventrals with a 

 light base and a blackish tip ; dorsal rays II, 11 to 13 ; pectoral rays 

 19 or 20 ; ventral fossa round ; interorbital narrower than eye ; 

 pectoral half as long as head haioaiiensis. 



When compared directly with paratypes of M. haivaiiensis^ the 

 type of M. nippo7iensis is found to diiler in the following characters : 

 The eye smaller, the head longer, especially the postorbital length; 

 the interorbital wider; the maxillary longer; the snout longer; the 

 spinules of the scales more numerous, more densely crowded and 

 shorter ; the soft dorsal rays fewer, 10, instead of 11 to 13 ; and in the 

 uniform coloration of the ventral fin. These differences are brought 

 out in the table of measurements, and have been verified in four com- 

 parable paratypes of 31. hawaliensis. 



Nothing can be said of the relationships of M. nipponeTisis with the 

 species found in the Indian Ocean, and identified with M. laevis by 

 Alcock ^ and Brauer.^ 



Dorsal II, 10; ventral, 9; pectoral, 20; 15 scales above lateral line. 



Contours of body little arched. Head rather pointed; snout high, 

 its bony tip above middle of eye ; preoral length of snout 2.2 in post- 

 orbital length of head ; preocular length of snout 0.4 in head ; orbit, 

 3.25; interorbital space wider than orbit; preopercular angle pro- 

 duced backward, the angle sharply rounded ; mouth large, the maxil- 

 lary half as long as head; teeth uniserial in lower jaw, becoming 

 irregular at the symphysis, and similar to but less strongly curved 

 than those of the outer premaxillary series, which is the stronger of 

 the two premaxillary series; the teeth about as in M. hawaliensis, but 

 much smaller than in the Philippine species, the longest one-tenth as 

 long as orbit; barbel slender, one-third the orbit; branchiostegals 

 seven; about nine short, movable, spinigerous gill-rakers on the 

 lower limb of the outer arch. 



Scales small, with numerous (about 20 to 30) small, suberect 

 spinules arranged in quincunx order in a diamond-shaped patch on 

 each scale ; these spinules more numerous, more crowded, and shorter 

 than in either larger or smaller specimens of M. hawaiiensis. An- 

 terior curve of lateral line low, about 1.5 times as long as the head. 

 Gular membrane naked; a series of scales on the branchiostegal 

 membrane over each ray ; inner edge of shoulder girdle mostly scaled, 

 as in the other Pacific species. 



1 Gilbert, Bull. U. S. Fish Comm., 1903 (1905), pt. 2, p. 677, fig. 265. 

 2Alcocl{, Ann. Mag. Nat. Hist. (6), vol. 4, 1889, p. 398, and (6), vol. 8, 1891, p. 123; A 

 Descriptive Catalogue of the Indian Deep-Sea Fishes, 1899, p. 119. 

 ^Brauer, die Tiefsee-Fische, p. 270. 



