104 PLAIN FACTS FOR OLD AND YOUNG 



own ova, thus being wholly independent. Human her- 

 maphrodites are usually so deformed that fecundation 

 is not effected, which is a fortunate safeguard against 

 the multiplication of such monstrosities. 



Complemental Males.— One species of barnacle 

 was for some time quite a puzzle to the zoologist, as 

 no male of the species could be found, hence no means 

 by which the eggs produced by the egg-bearing, or fe- 

 male, animal could be fecundated. At last. Professor 

 Darwin discovered, snugly hidden away in the corner 

 of a little i^ocket in the female, the male animal, so 

 unlike the female that it had never been suspected as 

 having any relationship ; but it proved, on examination 

 by dissection, to be a fully developed male. In some 

 varieties of this queer species, the female has been ob- 

 served carrying in this little pocket two or three of 

 these diminutive males. 



Development— After the union of the two elements, 

 known as fecundation, or conception, if the conditions 

 are favorable, development occurs; and the little 

 germ is in due process of time developed into an 

 individual which is an exact counterpart of its par- 

 ents. During this developmental process, the em- 

 bryonic being is variously treated by different classes 

 of animals. 



Unprotected Development.— Most fishes and rep- 

 tiles discharge their ova before fecundation, or soon 

 after, and pay no further attention to them. The fish 

 deposits its eggs in a little hollow scooped out in the 

 gravelly bed of a stream, or sows them broadcast upon 

 the waters. The turtle buries its eggs in the sand, and 

 leaves them to be hatched by the sun. The ostrich dis- 

 poses of her eggs in the same way. Many other species 

 of animals pay no regard to the protection of the germs 



