192 PROCEEDINGS OF THE NATIONAL MUSEUM. vol.51. 



Genus LIONURUS Gunther. 



Lionurus Gunther, Challenger Reports, vol. 22, Deep-Sea Fishes, 1887, pp. 

 124, 141. — Jordan and Evermann, Fishes of North and Middle America, 

 vol. 3, 1898, p. 2592 (fllkaHda). 



Nezumia Jordan, in Jordan and Starks, Bull. U. S. Fish Com., 1902 (1904), 

 p. 620. — McCuLLOCH, Records Australian ]Mus., vol. G, pt. 5, 1907, p. 34 

 {condylura). 



IMacruroplus Bleeker, Typi non nulli generici piscium neglecti, Verslagen 

 en Mededeelingen der k. x\.kademie van Wetenscliappen, Amsterdam, 

 (2), vol. 8, 1874, p. 369; leased on Macrotirus serratus Lowe, a species 

 not identified by other authors. Lowe's short description indicates that 

 his species is probably referable to this genus. If AI. serratus is ever 

 recognized, and proves to belong to the present genus, the name 

 Macruroplus must replace Lionurus. 



This genus as here characterized is very extensive, including most 

 of the species of Coryphaenoidinae which have seven branchiostegal 

 rays. The other genera with seven branchiostegal rays are closely 

 related to Lionurus. They are: ]\Ialacoce2:)hMus, Mataeocephxilus^ 

 Trachonurus., and Cetonurus. The species of Lionurus vary within 

 wide limits. On the one hand are species closely resembling Malaco- 

 cephalus., with a large, subterminal mouth, the maxillaries more than 

 one-third the length of the head, and other characters indicating a 

 natural group. These species are as follows: L. lucifer, L. nigro- 

 mffculatus, L. atherodon, L. petersoni^ L. occidentaUs., L. garmani, L. 

 ctenomelas, L. misal'ia., and L. ma(yfonema. On the other hand is a 

 series with a small mouth, the maxillaries being decidedly less than 

 one-third the length of the head (except in L. stelgidolepis) . At one 

 end of this series of small-mouthed forms are the more typical species, 

 such as L. hairdii, L. aequaUs, and L. sclerorhynchus., with conical 

 projecting snout and slender form, with the ventrals containing but 

 few rays and located below the pectorals, and with the origin of the 

 anal behind the first dorsah At the other end of the series are species 

 in which some or all of the following modifications are shown : An- 

 terior profile of snout subvertical; form robust; base of first dorsal 

 oblique; ventrals far anterior to pectorals; origin of anal under first 

 dorsal base; and the ventrals Avith an increased number of raj^s. Two 

 species, L. parvipes and L. cefo7iuropsis, are evidently related to 

 Cefonurops, as discussed in detail in the description of L. cetonu- 

 ropsis. Five sj^ecies with smooth scales are grouped in the subgenus 

 Lionurus., as originally proposed by Giinther. Generic rank is not 

 assigned them because the group is characterized only by the smooth 

 scales (a character which may haA'e been independently derived in the 

 different species). Moreover, the scales of the head are spinigerous 

 in L. liolepis. 



The dorsal spine is smooth or weakly armed in the subgenus Lionu- 

 rus. All the species of Lionurus with rough scales are provisionally 



