WANDERINGS OF A GIGANTIC AFRICAN SNAIL. 43 



The extended animal has a large and broad fleshy foot, five 

 inches in length and two inches broad. Individual shells of six 

 inches in length have occurred. The eggs of this snail are oval, 

 comparatively small, measuring about one-fifth of an inch in 

 long diameter. They are of a pale yellow colour, and have a 

 hard but thin shell. They are deposited in loose soil, just 

 below the surface. But what they lack in size they make up in 

 quantity. It appears that Achatina fulica attains its full growth 

 in two years time, but the half-grown snail (of one year) is 

 already sexually mature and capable of producing eggs. The 

 maximum number of eggs that may be produced at one time 

 has not been fully determined, but the animal has been known 

 to deposit at least one hundred in the first year, and, from 

 examination of several large clutches of eggs, it is probable that 

 the produce of the second year may be as high as five hundred. 

 Taking into consideration the fact that every individual is a 

 functional female, that the snails breed once a year and live for 

 at least two years, and allowing for only a brood of two hundred 

 in the second year, the rate of increase is a matter of simple 

 calculation. Excluding any casualties, we arrive at the astound- 

 ing total of 10,930,442,400 (roughly, 10,930| millions) as the 

 possible existing progeny of a single snail in the fifth year ! 

 There must, undoubtedly, be some efficient natural check to 

 counteract this amazing fertility. Otherwise the whole country 

 would very soon be buried under a mass of living snails. 



The adult snail, in Ceylon, appears to have very few enemies. 

 The Common Pond-Tortoise {Nicoria trijuga var. thermalis) is 

 the only animal that has been observed to attack it. But there 

 is probably a very heavy mortality in the early larval stage. A 

 species of ant (Phidologiton affinis) has been found swarming 

 amongst a batch of eggs that were just hatching out. Insecti- 

 vorous birds and carnivorous beetles may be expected to rank 

 amongst their natural enemies. 



Achatina fulica is a native of East Africa. It appears to 

 have found its way into Mauritius many years ago, and is now 

 said to be a common object of that island. With regard to its 

 history on the Indian Continent, there is a note by Godwin- 

 Austen (in the Proc. Mai. Soc. viii. p. 147, October, 1908) upon 

 the introduction of Achatina into Calcutta. He writes : — " When 



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