370 ANIMAL LIFE-HISTORIES 



LIFE-HISTORIES, &c, OF PRIMITIVE TRACHEATES 



(Prototracheata) 



We are here only concerned with the archaic and widely- 

 distributed form Peripatus, which has already been spoken of in 

 several connections, especially as being a sort of link between 

 Annelids and Arthropods. It is a light-shunning creature, and 

 though in all the numerous species the young are born alive, 

 there is a great deal of variation in respect to the amount of 

 food-yolk contained in the ftgg. This is large in amount in 

 species which live in the Australian region, much less in those 

 inhabiting South Africa, and practically absent in the American 

 forms. The newly -born young have been observed crawling 

 over the body of their mother, and as she is not entirely devoid 

 of means of defence (see vol. li, p. 360) this association may be 

 regarded as a protective measure. 



LIFE-HISTORIES, &c., OF CENTIPEDES AND MILLIPEDES 



(Myriapoda) 



The love of the beautiful is so marked a human characteristic 

 that it has had a considerable influence upon the course of scien- 

 tific research, though it has not swayed the professional zoologist 

 to the same extent as the amateur naturalist. But it cannot be 

 denied that the groups which include the more attractive-looking 

 animals have received an undue share of attention. This is the 

 case, for example, with Insects and Birds, while among the 

 former Butterflies have been studied much more exhaustively 

 than Flies or Bugs. Any investigator who desires to find a 

 field of activity likely to quickly yield a rich harvest of results 

 cannot do better than select a group of which the members are 

 superficially unattractive, or, still better, downright repulsive, re- 

 garded from the lay stand-point. No animals are " common or 

 unclean " in the light of science, and that any of them should 

 be so regarded is one of the undesirable items of the legacy 

 we have inherited from our prehistoric ancestors, whose stand- 

 point was purely utilitarian. These worthy but uncultured 

 gentlemen early discovered by painful experience that certain 

 creatures could bite, sting, or otherwise cause annoyance, and 

 in this we may discover the beginnings of a tendency to 



