Sharks by I'aul Budker, Sous-direcleiir an Museum National d'Histoire Naiurelle, Conseil lech- 

 niqiir du Minislere de la France d'Outre-AIer. 



The dog-fishes thai are found off the coasts of France are, strictly speaking, sharks in minia- 

 ture. Actually, this word " shark " only applies to Pleurotremata of a certain size, there being 

 a rather ill-defined length, over which the dog-fish has every right to be called " shark ". More- 

 over, it is difficult to say why, for there is no test enabling one to choose the adequate word 

 when faced with this hazy dividing line. According to Valery : " A subtler being (than man) 

 would doubtless have neither hard and fast units nor things that tend to be confused or assimi- 

 lated with one another when collections are made of them. Any concept (as the saying goes) 

 is expedient... ". 



In short, it doesn't really matter. It is only a question of vocabulary, which does not 

 preclude the shark group from having its own place among fishes and from having an unusual 

 and many-sided appeal. 



Because of their cartilaginous skeleton, which lacks true bone cells, and other characters 

 besides, sharks (and the related rays) are sometimes regarded as primitive creatures. That 

 may be countered by weighty arguments. The central and peripheral nervous systems, for 

 instance, are highly developed. With regard to the urinogenital system, this is markedly 

 superior to the precarious arrangements in teleost fishes. Within this very uniform group of 

 sharks, although it is made up of rather few species, can be found the most elaborate reproduc- 

 tive processes ranging as far as the placental type of viviparity. It is no wonder that biolo- 

 gists have chosen certain shark-like fishes as laboratory animals and that dog-fishes, that is, 

 those of a size allowing of ready handling, are a source for numerous and important scientific 

 works from year to year. 



But sharks have yet another claim they might boast of : the giant among fishes is one 

 of them. 



We know that the largest animals live in the sea. No other living creature has ever 

 attained the colossal dimensions of the blue whale, with a length that may exceed 100 feet and 

 a weight of about 100 tons. Certainly no fish can stand comparison with such a living mountain, 

 but the Goliath of gill-bearing vertebrates is " not to be sneezed at ". This is the shark, 

 Rhincodon lijpus, which easily holds the record for size. It is said to reach a length of nearly 

 60 feet. No one has been able to weigh such an animal, but we do know that one of 40 feet 

 scaled about thirteen tons. This fine fish is known as a whale-shark, not that it comes from 

 both whale and shark, as one ill-informed author once wrote. Our Rhincodon only comes from 

 the shark side. It is certainly one hundred per cent a fish and the word " whale " is only there 

 to give an idea of the unusual bulk of this very authentic shark. 



Its habits are rather odd, so far as the little we know of them goes. It is quite harmless, 

 feeding on plankton and seemingly leading a nonchalant sort of life. For the most part, 

 it lazes at the surface and this exposes it to a peculiar — and not infrequent — accident. When 

 it is slowly sculling with the dorsal fin out of the water, moving gently along as though it were 

 sunbathing, disdainful of all around it, a ship may collide with it full on the beam. This 

 has happened several times in the Red Sea and the Indian and Atlantic Oceans. In this encoun- 

 ter, the whale-shark is not generally cut in two. Because of the speed of the ship and the resist- 

 ance of the water, its body is brutally bent back and is held on either side of the bows. This 

 adventure always ends disastrously for the rammed fish. The ship comes to a stop and the 

 great body breaks, no longer being pressed against the hull. It slowly sinks in sight of the 

 witnesses of what may be considered a kind of traffic accident, in which the victim is entirely 

 to blame. 



The whale-shark is mainly to be found in tropical and subtropical seas. Nearer French 

 coasts a lesser " lord " the basking-shark (Celorhimis maximus) often appears. Its size, 

 while not reaching that of its enormous relative Rhincodon, is nevertheless very imposing. 

 Individuals of nearly 40 feet in length are not rare and it is a fact that a specimen of nearly 

 30 feet can weigh rather more than 4 tons. The basking-shark is livelier than the slow 



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