DESCRIPTIONS OF NEW GENERA AND SPECIES OF FISHES 

 FROM JAPAN AND THE RIU KIU ISLANDS. 



John Otterbein Snyder, 



Of Stanford University, California. 



This paper contains descriptions of 3 new genera and 23 new 

 species of fishes from Japan and the Riu Kiu Islands. They were 

 collected during the explorations of the United States Bureau of 

 Fisheries steamer Albatross in the north Pacific Ocean and along 

 the shores of Japan, in 1906. 



Family SYNGNATHID.E. 



MICROPHIS EXTENSUS, new species. 



This species is closely related to M. pleurotxnia of Hawaii. Two 

 examples of the latter agree with Giinther's description of the species 

 and differ from Microphis extensus in both color and form. The 

 Hawaiian species has the light bands very broad, thus confining the 

 light area on the side of the body to the dorsolateral row of plates, 

 and almost eliminating it from the breast and abdomen. The caudal 

 fin is without spots, having a dusky center and an indefinite, broad, 

 light edge. The ridges of the snout are smoother and the body is 

 considerably broader and heavier. The caudal fin is much less acute. 

 There are 24 to 25 dorsal rays in M. pleurotsenia, while M. extensus 

 has 21 or 22. 



Head 4.5 in length measured to base of caudal fin; depth 3.5 in 

 head; depth caudal peduncle 7.5; snout 2; eye 4; interorbital space 

 9; D. 22; A. 4; rings 19 + 15. 



Two strongly denticulated ridges extend from snout to inter- 

 orbital space; a dorsolateral denticulated ridge from tip of snout to 

 orbital rim, which is also serrated; upper edge of opercle with a 

 strong ridge from which many strias radiate. Osseus rings of body 

 with strong keels at the angles which have spines posteriorly, the 

 spines growing larger on the tail ; plates with only a trace of a median 

 keel. Dorsal located on seven rings beginning with the sixteenth., 

 Caudal fin pointed, the length contained about 1.4 times in the head. 

 Pectoral broadly rounded, about 2 in snout; nivs, 18. 



Proceedings U. S. National Museum, Vol. 40— No. 1836. 



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