xxu 



times many metres in height. It is then in the Ma- 

 dreporic Polypidoms, those that are wholly stony, 

 that we must seek for giants in this department of 

 the animal kingdom ; whilst their Polypi are so small 

 as frequently to elude the naked eye, and can only be 

 perceived by the help of glasses, and sometimes re- 

 quire very powerful microscopes ; in some groups 

 they even escape the power of our instruments, and 

 leave us only analogy and reason to demonstrate their 

 existence in the animal kingdom. It is however not 

 improbable that the Equinoctial seas may inclose 

 Polypi of sufficient magnitude to be observed without 

 the help of instruments ; but none of them exist on 

 our coasts, or in the north of Europe. 



UTILITY, GENERAL AND PARTICULAR. 



The unreflecting may ask, what is the utility of 

 these creatures ; too small to afford material nourish- 

 ment to others, yet capable of rendering venomous 

 those which partake of the little they can supply t De- 

 voured by fishes, the Polypi have rendered those 

 fishes so unwholesome, that soldiers who have fed on 

 them have experienced maladies so serious and so 

 general, that the expedition for which they were in- 

 tended has been necessarily given up. 



Other species of fish, and in particular the mollusca 



