MICHIGAN" STATE POMOLOGICAL SOCIETY. 303 



many of which may, for j)ractical purposes, be grouped into 

 one family — as, for instance, the seven families of Digger- 

 wasps, and the five large Families which have all the same 

 habits as the true or genuine Ichneumon-flies. Many more 

 may be neglected as small, rare, or unimportant ; so that prac- 

 tically there will remain about a hundred family types to be 

 learned. Each family, as Agassiz has well remarked, may, 

 with a little practice, be distinguished at a glance by its 

 general appearance, just as every child, with a little practice, 

 learns to distinguish the family of A's from the family of B's, 

 and these from the family of C's in the alphabet. There is 

 the Old English A, the German text A, and a host of orna- 

 mental A's, both in the capital letter and the small or '•' lower- 

 case" letter, as the printers call it; but the family likeness 

 runs through them all, and it is astonishing how quick a child 

 learns to distinguish each family type. It is true there are a 

 few abnormal or eccentric insects — there were some which 

 deceived even Linnajus — which put on the habit of strange 

 families, just as an eel, which is a true fish with fins, puts on 

 the habit of a snake, — a reptile without fins. But these are 

 the exceptions and not the rule. 



Now it is wisely ordained that every family, as a general 

 rule, has not only a distinctive family appearance, but also 

 distinct family manners. For example, nobody ever saw an 

 Ichneumon-fly construct a nest and provision it with insects, 

 as does a Digger-wasj) ; and nobody ever saw a Digger-wasp 

 desposit its eggs in the body of a living insect at large in the 

 woods, as an Ichneumon Fly does. But each family maintains 

 its peculiar family habits, and cannot be induced to deviate 

 from them. 



So universally is this the case, that if you bring me an 

 insect which I never saw in my life, I will tell you half its 

 history at a glance. It is this '•' unity of habits,'' this beauti- 

 ful provision of nature, definite family likeness, accompanied 

 by definite family habits, which so simplifies the task of the 



