NO. 23 NEW GENUS OF OPISTHOGNATHID FISHES MYERS 3 



lb. Dorsal spines flexible, not pungent ; cheeks and opercles naked. 

 3a. Dorsal spines distally split into 2 lateral segments. 



Stalix Jordan and Snj'der 

 3b. Dorsal spines distally entire. 



4a. Trunk naked anteriorly Merogyvimis Ogilby 



4b. Trunk fully scaled. 



5a. Maxillary shorter than head, its distal ex- 

 tremity truncate or notched Gtiathypops Gill 



Sb. Maxillary greatly produced backward in a 

 flexible lamina, about as long as head. 



Opisthognathus Cuvier (Oken) 



LONCHISTIUM, n. gen. 



Dorsal and anal spines sharp and stiff. Posterior part of cheeks 

 scaled and a patch of 9 scales on the upper part of the opercle. Scales 

 of body moderate in size, about 40 in a longitudinal series to base of 

 caudal. Gill rakers 38 on first arch. Dorsal with 11 spines and 12 

 soft rays. Anal with 2 spines and 12 soft rays. Head heavy and thick, 

 not nearly so compressed as in Lonchopisthus. Eyes very large. Geno- 

 type, L. Icviiir. 



LONCHISTIUM LEMUR, n. sp. 

 Figure i 



Uolotype. — U.S.N.M. no. 93459 (Field no. 722), 35 mm standard 

 length ; from Johnson-Smithsonian Deep-Sea Expedition station 105, 

 off Punta Boca Juana, Puerto Rico, latitude 18° 30' 50" N., longitude 

 66° 13' 20" W., to latitude 18° 31' 30" N., longitude 66° 14' 55" W., 

 March 8, 1933, oyster dredge, 150 fathoms. 



Description. — Unfortunately, the single specimen on which this 

 species is based is in rather poor condition, due largely to its having 

 been taken in the oyster dredge on very rough bottom. The fins are 

 more or less broken, many of the scales have fallen, and the intestine 

 was removed in search of parasites when the specimen was fresh. It 

 is thus impossible to be certain of the length of the caudal and the 

 shape of the dorsal and anal fins, but, after careful examination of 

 the fish, I believe I have succeeded in restoring very nearly the original 

 form of the fins in the accompanying sketch. 



Dorsal XI-12. Anal II-12. Pectoral 17 or 18. Pelvic I-5. Caudal 

 22, counting rudimentary rays above and below. Scales mostly lost, 

 40 to 42 in a longitudinal series frcjm uj^per part of gill opening to 

 end of hypural fan. 



