LECTURE VII. 311 



stances. Those of the mushroom kind are 

 perhaps as good an instance as can be pro- 

 duced. The multitudinous seeds appear 

 to the naked eye a most subtile and light 

 dust, which when diffused through the air, 

 forms an evanescent cloud. 



Nature has made also some animals mo- 

 noicous, and placed the male and female 

 parts in the same individual ; though in 

 general she has allotted them to different in- 

 dividuals, particularly in the higher classes, 

 and given to each its distinguishing sexual 

 character. The male is in general the largest 

 and the strongest ; but there are exceptions 

 to this rule, showing that this ordinance is 

 not the result of necessity. As the vital 

 powers of animals speedily decay and shortly 

 cease, the production of successors becomes 

 a most important object.* Nature has there- 

 fore given animals of different sexes the 

 strongest propensities, so to communicate 



* How exceedingly various is the duration of life in 

 different vegetables and animals ! Yet for this variety 

 we can discern no adequate cause. 



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