GARMAN: THE CHIMAEROIDS. 249 



tuilinallv and pointin;^; upward, forward, or backward. This armature con- 

 tinues to within a short distance in front of the end of the tail, and behind its 

 point of disappearance there is a low ridge to the extremity. The subcaudal 

 fin is much deeper than the supracaudal ; it originates below the termination 

 of the second dorsal, rises gradually, becomes deepest in the anterior half of 

 the length, then slowly tapers to the caudal filament. The pectoral fins are 

 long, more than two and one-half times as long as wide, and when extended 

 the sharp outer angle reaches to the bases of the ventrals. The length of the 

 ventral fin is about equal to the height of the first dorsal and the width is less 

 than half of the length : tlie claspers are simple, slender, nearly four times as long 

 as the eye, subround in trans-section, very muscular near the base, enlarged 

 into an oblong rounded spine-covered bulb at the extremity, and jointed so as 

 to be turned directly forward, Plate 3, Figures 1, 4 and 5 ; each ventral tenacu- 

 lum has three strono- hooks on its inner ed^re. There is no distinct anal tin. 



On the sides and the lower surfaces thecolor is a light olivaceous or plum- 

 beous more or less silvered; toward the back and on the tail it is more brown ; 

 the fins are darker to blackish outwanl. 



Total length, 35.5 ; snout, G.5] snout to dorsal spine, 10.8; snout to second 

 dorsal fin, 15.4; snout to upper caudal armature, 24.4; snout to vent, 17.2. 

 depth, 3.5; length of pectoral fin, G 5 ; length of ventral fin, 3 5 ; snout to anal, 

 20 ; snout to pectoral fin, 10.3; snout to eye, 8.3 ; length of orbit, 0.8; length of 

 dorsal spine, 3.6 ; length of clasper, 3.1 ; width of gill aperture, 1 1 ; width of 

 body or head, 2.4 ; length of cephalic tenaculum, 0.6 ; length of head, 0.5 ; depth 

 of body at axil of ventral fin, 2.2; width above axil of ventral fin, 1.1 : and 

 length of caudal section (probably after a slight loss), 17.5 inches. 



Specimen described from Tokyo, Japan. Other specimens are said to have 

 been purchased in the same market that were caught near by, in water of two 

 hundred fathoms or more in depth, off oNlisaki. 



. Lateral Canal System, Plate 1, Figure 1 ; Plate 2; Plate 4, Figure 3. 



The structures ami functions of these canals are similar in the Chimaeroids 

 and the Plagiostomia. The excessive differentiations of structure and the com- 

 plexities of function obtaining on some of the deep-sea bony fishes do not occur 

 on either of them. In tlie distribution of the canals, however, there are cer- 

 tain peculiarities in all the members of the group that distinguish the Chimae- 

 roids from both Plagiostomes and bony fishes. A description of the system on 

 Rhinochimaera applies fairly well to all the genera of its kindred, for even in 

 the strange form of Callorhynchus one has but to apply the foliation of the 

 snout to the lower side of the rostrum to make the similarity at once apparent. 

 For comparisons and for nomenclature see this Bulletin, Vol. XVIT., No. 2, Gar- 

 man, 1888, On the Lateral Canal System of the Plagiostomia and Holocephala, 

 Plates T. to LTIL, and Mem. ]\Ins. Comp. Zool, Vol. XXIV., Garman, 1899, Deep 

 Sea Fishes, Plates LXIX. to LXXXIV. On the Chimaeroid the aural branch 

 of the system, which crosses the back of the head, lies in front of the orbital, 



