alive, and for an hour or more stood watching their 

 strange movements. The largest was eighteen inches in 

 length and five in height, yet so thin that, it weighed 

 only two pounds. The reporter was not far from right 

 in saying that its shape was like that of a flat-fish; in 

 fact a rough idea of its appearance may be gained by 

 imagining a flounder having symmetrical sides and 

 swimming in an upright position, 



The most noticeable feature about the fish is its 

 mouth, and this is still more striking if the skin 

 and flesh are removed 'and we get a good view of 

 the skeleton. The bones of the upper jaw are 

 closely u^ite? and in the lower are completely grown 

 together, instead of being separate as they are in most 

 fishes. This gives the jaws an extremely powerful grip, 

 their action being much like that of a pair of nut- 

 crackers, and they are set with rows of teeth which, 

 though thin , are very sharp and strong. Thus provided 

 the fish browses with ease among the rocks upon its 

 pasturage of barnacles, snails and mussels. A similar 

 union of the bones of the mouth is found in the sun- 

 fishes, box-fishes, swell-fishes, porcupine fishes and 

 trunk-fishes, as well as in the ^ile-fishes, and has given 

 the name to the Order in which they are all included — 

 that of the Plectogimthi (plectos, conjoined, and gnatluri, 

 the jaws). If the hand is drawn along the side of the 

 fish it feels a surface like that of coarse sand-paper, and 

 if we examine the scales, which, instead of overlapping 

 each other as in ordinary fishes, are minute and placed 

 side by side like those of a shark, we find thac each 

 is provided with a rough protuberance or knob. The 

 fishes thus roughly clad are known as "file-fishes" and 

 constitute the Sub-order Scleroderma [sMeros, rough, and 

 derma, skin). The carpenters in the West Indies often 

 use their skins for polishing wood-work. In front of 

 the dorsal fin we notice a strong, rough spine, about 

 two and one-half inches long, resembling the trigger of 

 a gun. It is arranged to fold into a groove in the top of 

 / the back, like a jack-knife blade into its handle, so that 

 it shall offer no resistance when the fish is swimming 

 through the water. A peculiar knack must be used, 

 however, in shutting it down, for it is like a gun-trigger 

 in the mechanism of its hinge as well as in its appear- 

 ance. At its base the spine is expanded and divides into 

 two arms, the extremities' of which approach each other 

 and embrace the crest of the super-occipital bone, which 

 has upon each side a depression to receive the terminal 

 knobs; a long, curved spur, which describes the arc of 

 one-third of a circle, projects backward from the spine, 

 at a point just above the junction of its basal arms, and 

 is received into a curved mortice which extends forward 

 under the super-occipital crest, thus clamping the spine 

 down upon its seat and forming a hinge which allows 



