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POPULAR SCIENCJS MONTHLY. 



water, their axes making various angles with the horizontal, their 

 pectorals folded to their sides. When swimming slowly it is chiefly 

 by the use of the pectorals. The strokes of the pectoral are lazily 

 given, and the fish glides on after a stroke till its impetus is ex- 

 hausted, when another stroke is delivered. The fishes frequently 



Fio. 4. — Ipiiopx Mnrrajji, living at a depth of 1,.')00 to ii,100 fathoms. 

 Fio. 5. — l!lilnri>i)htlutliniiti (jraciliif, from 1,100 fathoms, off JSew Zeuhtiul. 



roll slightly from side to side at the exhaustion of the result of 

 a stroke. When swimming rapidly the pectorals are folded 

 to the sides, and their locomotion is then similar to that of a 

 salamander — by the motion of the tail. They readily adjust them- 

 selves to different depths, and are usually perfect philosophers, 

 quiet, dignified, unconcerned, and ini perturbed, entirely different 

 from such eyed species as minnows and sunfislies which are some- 

 times found in caves and which are much more readily disturbed 

 by any motion in the water, making it almost impossible to capture 

 them when found in the caves. The pectorals are also almost ex- 

 clusively used when quietly rising in the water. At such times 

 the pectorals are extended laterally and then pressed to the sides, 

 beginning with the upper rays. A downward stroke is delivered 

 in this way not quickly, but with apparent lazy deliberation. In 

 swimming the pectorals are brought forward upper edge fore- 

 most. The center of gravity seems to be so placed in regard to 

 their various axes that the fish does not lose its balance whatever 

 its position. They float horizontally in the water without any 

 apparent effort to maintain their position, or with the main axis 

 inclined upward, with the snout sometimes touching the surface 

 of the water, apparently lifeless. Once one was seen resting on 

 its tail in a nearly vertical position, and one while quietly swim- 

 ming was once seen to leisurely turn a somersault and swim on 

 undisturbed. At another time the same individual rolled com- 

 pletely over. When one of them is kept out of the water for a 

 short time it frofjuently goes in a corkscrew-shaped path through 

 the water, continually spinning around its long axis. In their 

 quiet, floating position it is difficult to determine whether they are 

 alive or not. 



