TWO YOUNG NATURALISTS. 25 



" Are the representatives ! " cried Rene. " I really 

 think you do the sand-eel a great honour." 



" We have seen the Annulosa in two of their chief 

 forms: crabs (Crustacea), marine worms (Annelida). 



"The shells on which we walked, and which make 

 up a large portion of the sands, belong to the Mol- 

 lusca. 



"Finally, the star-fish, the sea-urchin, and sea- 

 anemone are clearly and unmistakably radiates. So 

 that you see the collection is complete." * 



" I see that I do not yet see. How are the radiates 

 distinguished ? " 



"By the fact that their organs, instead of being 

 arranged on either side of the body in pairs, are 

 grouped round a central axis, so as to give rise to a 

 radiate or globular form." 



"Very good. And the Annulosa?" 



u The Annulosa have a higher structure : their 

 organs are arranged in pairs, they have no internal 

 skeleton, but their body is made up of a series of rings 

 placed one behind another, sometimes soft, as in the 

 case of the worms, but more often hard (in insects), 

 even shelly (in most of the Crustacea)." 



* The four branches here indicated as composing the animal kingdom are 

 those proposed by Cuvier, the great French naturalist. Modern zoologists 

 have divided some of these groups, considering them not to be sufficiently 

 natural, and nine primary divisions of the animal kingdom are now accepted, 

 viz., Protozoa, Coalenterata, Echinodermata, Vennes, Arthropoda, Mol- 

 luscoidea, Mollusca, Tunicata, and Vertebrata. Some, however, do not 

 adopt the division of the Mollusca into three groups, and accept only seven 

 sub -kingdoms. TEANSLATOB'S NOTE. 



