THE PROBLEM OF PARASITISM 203 



compare the attractive free stages of some of them 

 with the ungraceful, bloated, absorbent masses of 

 tissue which they may become as adults. The ugli- 

 ness is Nature's stamp of degeneracy and dishonor; 

 it is the natural result of retrogression, involution, 

 sluggishness, and overfeeding. Beauty is universal 

 among free-living, full-grown, wild creatures in a 

 state of health and away from man's ringers; ugli- 

 ness is the brand of failure. As George Meredith 

 said: "Ugliness is only half-way to a thing." It 

 is interesting to notice that the dodder and mistletoe, 

 which every one recognizes as beautiful, are only 

 partial parasites. Inextricably associated with the 

 purely aesthetic repugnance is the feeling that an 

 organism which does not fend for itself is a sort of 

 contradiction in terms. 



To many minds, indeed, the darkness of the 

 shadow is in the inconsistency between the parasitic 

 regime and Nature's usual insistence on a strenu- 

 ous life. This must be admitted, and yet there are 

 extenuating circumstances. In the struggle for 

 existence the organism finds itself beset by environ- 

 ing difficulties and limitations, and one of the re- 

 actions that sometimes pay is to become a parasite. 

 But the struggling creature does not see it .in our 

 light, and has no prevision of the facilis descensus 

 on which it sets foot. It may try to survive inside 

 a larger organism which has swallowed it, just as 

 another may try to survive in a cave, and another 

 in a warm spring. In its searching for food and 

 shelter it may discover in or on another organism 



