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PROCEEDINGS OF THE NATIONAL MUSEUM. 



VOL. XXXII. 



the rays are 10 nun. long-. The ventral fins are gone, but a portion of 

 the ventral plate is present. Its outer surface was sculptured. The 

 anal fin is disturbed and a part missing. The caudal is preserved. 

 The length of the fish from the snout to the base of the caudal is 51 

 nnn. ; the length of the head, 14.5 mm. ; the depth of the body, 9.5 mm. 

 There is no trace of either lateral armor or a caudal keel. 



Fig. 1.— Skeleton of gasterostei'S wii.liamsoni i.eptosomus, (Typej ,•!.'. 



The second (Cat. No. 538T, U.S.N.M.) laciis most of the head (fig. 2). 

 The length from the shoulder girdle to the base of the caudal is 38.5 

 mm.; the depth is 10 mm. The first dorsal spine is 3 mm. long; the 

 second 5 mm. ; the third is short and curved. There are 10 soft dorsal 

 rays. The ventral spines have a length of 7 mm. and the ventral 

 plates a length of 11 nnn. The anal spine is short and curved, and 

 there are counted 9 soft rays, with an interhaemal spine for a tenth. 



Fig. 2. — Nearly complete skeleton ov gastekosteis wu.i.iamsoxi leptosomus. xU- 



Below and in front of the second dorsal spine are remains of three 

 plates belonging to the lateral armor, ])ut there is no indication of the 

 cautlal keel. 



The third (Cat. No. 5388, U.S.N.M.) presents the head, the second 

 dorsal spine, and a portion of the ventral plate. The spine is -4 nnn. 

 long. The ascending process of the ventral plate is sculptured. 



