342 NATURAL HISTORY. 



dangerous forms (Synanceia) ; for in these there is a poison-gland (Fig. 318) 

 on each of the dorsal spines, and this may cause a wound always as painful 

 as that of a scorpion, and sometimes followed with fatal effects. In still 

 other related fishes the gill-covers, in addition, have poison-organs. 



Our figure on the preceding page shows a strange fish, — strange both 

 in appearance and in habits. It has no common name, and so the scien- 

 tific Periophthahnus must suffice. This name has reference to the large 

 eyes, which are exceedingly movable, and can be thrust far out of their 

 sockets or retracted at will. The fishes live almost as well out of water 

 as in it, and they are fond of wandering about on the mud-flats, hopping 

 freely by means of their strong fins and tail. They feed on the shore life, 

 — the beach-fleas and molluscs, — and their rapid motions enable them to 

 escape any ordinary enemy. With one exception all belong to the shores 

 of the Indian Ocean. 



True parasites are exceedingly uncommon among fishes, but there is 

 one instance, not exactly of true parasites, which is very interesting from 

 the peculiar homes that it seeks. In the Mediterranean it lives, like a 

 hermit in its cave, inside the body of the sea-cucumbers. It makes its 

 entrance through the anal opening, and with its head toward the vent 

 watches for its food. 



The suck-fish, or stay-ship, are strange fish, five species of which occur 

 on our coasts. Their peculiarity lies in the fact that the first dorsal 

 fin loses its character of a fin, and is converted into a sucking-organ, 

 placed on the top of the head and extending a short distance on the back. 

 With this sucker it attaches itself to any floating object, especially sharks 

 and sword-fish, and thus gaining a free ride. But what advantage this is 

 to the fish it is not easy to see ; for they are strong swimmers, and it would 

 hardly seem necessary that they should require such a peculiar style of 

 locomotion. Besides fish, they sometimes adhere to other objects, and the 

 sailors are fully persuaded that when they fasten themselves to the hull of 

 a ship, her progress will be greatly retarded, no matter how strong the 

 breeze. 



It is stated that this peculiarity is in some places made of use in fishing 

 for turtles. One of the earliest references to this is transcribed from the 

 pages of Mr. Goode, who in turn takes Ogilby's 'America' of 1671, where 

 it is accompanied by a very curious figure of an Indian fishing. 



" Columbus, from hence [from Cuba] proceeding on further Westward, 

 discover'd a fruitful Coast, verging on the Mouth of a River, whose Water 

 runs Boyling into the Sea. Somewhat further he saw very strange fishes, 

 especially of the Guaican, not unlike an Eel, but with an extraordinary 



