MUSEUM OF COMPARATIVE ZOOLOGY. 11 



this changing of the direction of the prey is all accomplished at the time 

 of the renewals of the grasp. 



After the fish has been thus nearly oriented, its head end is introduced 

 into the throat by a single forward lunge on the part of the gar-pike. 

 These forward movements are continued for some time, the jaws being 

 slightly opened at each lunge. When the head is well introduced into 

 the gullet, the jaws are no longer suddenly opened and closed, but re- 

 main more or less gaping, while the prey slowly disappears, doubtless 

 being drawn on by peristaltic motions of the gullet. There are usually 

 slight motions of the jaws during this latter process, — a slow opening 

 and partial closing of them. The movement of the lower jaw is some- 

 what unsteady, almost tremulous, a peculiarity which is also seen, al- 

 though not so distinctly, at other times than when feeding. 



The advantage of a great divaricability of the rami of the lower jaw 

 and of the fulness of the skin connecting them is at once apparent 

 when a comparatively large fish is half swallowed, for then the thin 

 membranous floor of the mouth is greatly distended and the rami 

 pushed far apart. A side view of the head of the fish then resembles 

 somewhat the appearance of the throat of a feeding pelican. 



Gar-pikes sometimes take food which they apparently discover to be 

 objectionable only after they have partially swallowed it. In such cases, 

 it is ejected from the throat with a sudden jet of water. 



They do not hesitate to snap at each other when kept in confinement, 

 as I have many times observed, and as the mutilated condition of the 

 fins, and especially of the tail, makes very evident. I think it may be 

 inferred that they are not altogether free from danger from their own 

 kind when living in their natural haunts, for they always show a remark- 

 able sensitiveness to being touched in the region of the tail. The caudal 

 filament especially is so sensitive that the slightest touch from a foreign 

 body causes the fish to dart away with utmost speed, whereas one may 

 touch any other part of the body with comparatively little effect. The 

 young fishes become easily accustomed to the touch of the hands, and 

 may even be lifted altogether out of the water without offering any 

 resistance, provided it be done gently and without any quick motion. 

 But none of them ever become so tame as to allow the slightest contact 

 with the caudal filament without immediate efforts to escape. It is 

 almost invariably the tail end which is snapped at by their mates, 

 though I have a few times seen two individuals with interlocked jaws 

 carry on a short contest without fatal results to either. I have known 

 of only one case in which a gar-pike swallowed one of its mates. Near 



