356 REVIEWS — NATURAL HISTORY OF CEYlrON. 



found in the Atlantic, nor even on the western shores of tropical America. And 

 if, as has been stated, they have been seen on a late occasion in considerable 

 numbers in the Bay of Panama, the fact can only be regarded as one of the rare 

 instances, in which a change in the primary distribution of a race of animals 

 has occurred, either by an active or a passive immigration. Being exclusively 

 inhabitants of the sea, they are liable to be swept along by the influence of 

 currents ; but to compensate for this they have been endowed with a wonderful 

 power of swimming. The individuals of all the groups of terrestrial serpents 

 are observed to be possessed of this faculty to a greater or a less degree ; and 

 they can swim for a certain distance without having any organs specially modi- 

 fied for the purpose ; except, perhaps, the lung, which is a long sac capable of 

 taking in a sufficient' quantity of air, to keep the body of the snake above water. 

 Nor do we find any peculiar or specially adapted organs even in the fresh-water- 

 Bnakes, although they can catch frogs or fishes while swimming. But in the 

 hydrophids, which are permanent inhabitants of the ocean, and which in an 

 adult state, approach the beach only occasionally, and for very short times, the 

 tail, which is rounded and tapering in the others, is compressed into a vertical 

 rudder-like organ, similar to, and answering all the purposes of, the caudal fin 

 in a fish. When these snakes are brought on shore or on the deck of a ship, 

 they are helpless, and struggle vainly in awkward attitudes. Their food con- 

 Bists exclusively of such fishes as are found near the surface ; a fact which 

 affords ample proof that they do not descend to great depths, although they can 

 dive as well as swim. They are often found in groups during calm weather, 

 Bleeping on the sea ; but owing to their extreme caution and shyness, attempts 

 to catch them are rarely successful ; on the least alarm, they suddenly expel the 

 air from their lungs and descend below the surface ; a long stream of rising 

 air-bubbles marking the rapid course which they make below. Their poisonous 

 nature has been questioned ; but the presence of a strong perforated tooth and 

 of a venomous gland sufficiently attest their dangerous powers, even if these 

 had not been demonstrated by the effects of their bite. But fortunately for the 

 fishermen, who sometimes find them unexpectedly among the contents of their 

 nets, sea-snakes are unable, like other venomous serpents, to open the jawa 

 widely, and in reality they rarely infiict a wound. Dr. Cantor believes, that 

 they are blinded by the light when removed from their own element ; and he 

 adds that they become sluggish and speedily die." 



We will positively resist the temptation to extract anything relating 

 to fishes, mollusca, insects, &c., that we may in conclusion give our 

 author's account of the land leeches which to many readers will be as 

 novel and wonderful as anything he relates :- — 



" Of all the plagues which beset the traveller in the rising grounds of Ceylon, 

 the most detested are the land leeches. They are not frequent in the plains, 

 which are too hot and dry for them ; but amongst the rank vegetation in the 

 lower ranges of the hill country, which is kept damp by frequent showers, they 

 are found in tormenting profusion. They are terrestrial, never visiting pouda 



