TWO YOUNG NATURALISTS. 67 



other day how the mollusca may be recognised and 

 into what categories they are divided." 



"The mollusca are, as their name indicates, creatures 

 with soft bodies and without either external or internal 

 skeleton, for it would be going too far to call the one 

 bone of the Cephalopoda a skeleton. Some of them 

 are uncovered, others are protected by a shell. They 

 are divided into four classes : first, the Cephalopoda, 

 which have the feet placed around the head. To 

 these belong the Octopus, the Sepia, the squid." 



"These certainly ought to be the most fleet of 

 animals," interrupted Eene. 



" ? ? ? ?" 



" Because they have always their legs on their 

 neck." * 



" Is it impossible to induce you to be serious ? The 

 second class is that of Pteropoda, a not very numerous 

 group of animals inhabiting the great seas, having a 

 fin placed on each side of the mouth : examples, Clio 

 and Hyale. We shall not meet with any of them in 

 the waters of the Channel, so I pass them by. 



" Finally, the last two classes are named respectively 

 the Gasteropoda, from the mode of progression of the 

 animals that compose the group, the lower part of the 

 body forming a sort of sucker or fleshy foot, by the 

 aid of which they drag themselves hither and thither. 



* Rene's joke is lost in translation. To " have the legs on the neck " is 

 in English to take to one's heels. Thus the Cephalopoda are, in French, 

 always taking to their heels, but in English this is not the case. 



