18.2 NOTES. 



name has, through mistake, obtained a measure of 

 notoriety not due to it. 



8. The letters and fractional numbers frequently- 

 set after the references to the figures, indicate 

 the ratio which the figures bear to the size of 

 nature : thus n. s. signifies " natural size ;" i, that 

 the figure is one-fifth of natural size; and y 3 , that 

 it is magnified ten times. 



9. For all hard names, look first for an expla- 

 nation in the notes with which each Class is 

 introduced; if it is not explained there, search 

 for it in the Glossary. 



10. Finally, do not be discouraged if you meet 

 with difficulties ; whatever is worth attaining is 

 worth persevering for ; there is no royal road to 

 science. It would be well to practise upon some 

 common animal whose name you already know ; 

 for example, the Prawn (Palwmon), the Lobster 

 (Homarus), the Crab (Cancer), the common Smooth 

 Anemone (Actinia), the Sea-urchin (Echinus). 

 Take either of these, and compare it with the 

 characters given of its Class, its Order, its Family, 

 its Genus : — you will not recognise all, but you 

 will find enough to afford you very useful practice, 

 and to increase your experimental acquaintance 

 with Zoology. 



