110 THE PLACOID BRAIN. 



cisecl by these creatures seems more extraordinary stilL The 

 hatred which the fisher bears to them arises not more froti\ 

 the actual amount of mischief which they do him, than froi.! 

 the circumstance that, in most cases, they persist in doing i 

 with complete impunity to themselves. I have seen, said an 

 observant Cromarty fisherman to the writer of these chapters, 

 a pack of dog-fish watching beside our boat, as we were haul- 

 ing our lines, and severing the hooked fish, as they passed 

 them, at a bite, just a little above the vent, so that they 

 themselves escaped the swallowed hook ; and I have frequently 

 lost in this way no inconsiderable portion of a fishing. I 

 have observed, however, he continued, that when a fresh pack 

 of hungry dog-fish came up, and joined the pack that had 

 been robbing us so coolly, and at their leisure, a sudden rash- 

 ness would seize the whole ; the united packs would become 

 a mere heedless mob, and, rushing forward, they would swal- 

 low our fish entire, and be caught themselves by the score 

 and the hundred. "We may see something very similar to 

 this taking place among the shrewder mammalia. When 

 pug refuses to take his food, his mistress straightway calls 

 upon the cat, and, quickened by the dread of the coming 

 rival, he gobbles up his rations at once. With the compara- 

 tively large development of brain, and the corresponding ma- 

 nifestation of instinct, which the true placoids exhibit, we find 

 other unequivocal marks of a general superiority to their class. 

 In their reproductive organs they rank, not with the common 

 fishes, nor even with the lower reptiles, but with the Chelo- 

 nians and the Sauria. Among the rays, as among the higher 

 animals, there are individual attachments formed between 

 male and female : their eggs, unlike the mere spawn of the 

 osseous fishes, or of even the Batrachians, are, like those of 

 the tortoise and the crocodile, comparatively few in number, 

 and of considerable size ; their young, too, like the young of 

 birds and )f the higher reptiles, pass through no such me- 



