238 PROCEEDINGS OF THE NATIONAL MUSEUM VOL. 103 



Monocentris reedi, new species 



Plath 1 

 Mononniiis japo/'iacs, Fovdfv, Fish C'ultiirist, (Philadelphia), vol. 34, Nt). 9, 



p. 05, f"g., May J 955 (Juan P'crniindoz Islands, Chile). 

 Monorenlris, Ptoed, Iiiv. Zool. Chiloias, vol. 2, Xo. S, p. V.M, fig. 1955 (.Juan 



Ferndndez Islands, Chile). 



ITolotypk: USNM 164227. A dried spocimen 92 mm. in standard 

 lenglli, taken in lobster traps in February 1955 off Mas a Tierra 

 Islan([, Juan Fernandez Islands, off the eoast of Chile, at depth of 

 200 to 250 meters by fishermen. 



Descriptiox: The followhig counts were made: Dorsal rays 

 VI,ii,10, with a rudhnent of a seventh spine; anal i,10; pectoral 

 ii;12-ii,12; pelvic I.,iii; plates along lateral line from rear of head to 

 base of caudal fin 18 on one side, 19 on the other; plates in a row from 

 soft dorsal origin to lateral line 4, and from anal origin to lateral line 

 (obliquely forward) 4. The details of arrangement of plates are 

 illustrated in the photographs. 



Certain measurements were made on the holotype, and these are 

 expressed in thousandths of the standard length of 92 mm. as follows: 

 Length of head 392; greatest depth 456; least depth of caudal pe- 

 duncle 92; length of caudal peduncle from base of last anal ray to 

 midbase of caudal fin 174; diameter of eye 130; length of snout 125; 

 maxillaries or distance from tip of snout to rear of maxillary 201 ; 

 bony interorbital space 120; length of first dorsal spine 102, of longest 

 or second dorsal s])ine 267; length of pelvic spine 310. 



See table 1 for counts made on Monocentris japonicus (Houttuyn) 

 and M. reedi, new species. 



Discussion: The family Monocentridae has referred to it two 

 genera — Monocentris Bloch and Schneider with Gasterosteus japonicus 

 Houttuyn as genotype, from the western Pacific, and Cleidopus De 

 Vis with C. gloria-maris De Vis as genotype, from Australia. The 

 genus Cleidopus differs from Monocentris in having a patch of vomerine 

 teeth, a luminous organ on each side of the mandible, a very narrow 

 preorbital bone instead of no teeth on the vomer, no luminous organ 

 on the mandible, and a broad preorbital bone. 



Powell (Rec. Auckland Inst. Mus., vol. 2, p. 151, pi. 36, 1938, type 

 locality Opoutama Beach, 40 miles south of Gisborne, New Zealand) 

 described Cleidopus neozelanicus. He points out that this species is 

 intermediate between Monocentris and Cleidopus. It agrees mth 

 Monocentris in having a broad preorbital and no luminous organs on 

 mandible. It agi-ecs with Cleidopus in having vomerine teeth. With 

 this intermediate species, ]:>erhaps ns Powell suggests, Cleidopus 

 should be referred as a synonym to Monocentris. Anyway, regardless 

 of the generic affinities which I cannot work out because of lack of 

 material, neozelanicus differs from reedi in having vomerine teeth, a 



