LIFE AND DEATH. 129 



the whole body breaks into many pieces, and the superficial layer 

 gradually atrophies, so that it dies before the eggs are extruded.' 

 In Julin's account 1 , upon which Gotte bases his statements, there 

 are, however, some not unimportant differences. For instance, the 

 eggs are not extruded at all, but embryonic development takes 

 place within the body of the mother, which has previously under- 

 gone spontaneous division into several pieces. In this case, the eggs 

 differ from those of the other female form, inasmuch as they do not 

 constitute the whole of the endoderm, but are embedded (as was 

 stated above) in a fairly voluminous granular mass at the expense 

 of which, or at least by means of which, they are nourished ; for 

 they increase considerably in size during their development. But 

 not only this granular mass, but ?11 the layers of the body of the 

 mother, even the ectoderm, persist during the embryonic develop- 

 ment of the offspring. Indeed, the ectoderm must continue to 

 grow during the division of the mother animal, for it gradually 

 covers in the products of division on all sides, and, by means of 

 its cilia, causes the animal to swim about in the fluids of its host. 

 After some time the cilia are lost, and the separate parts into 

 which the mother animal has divided, fix themselves upon some part 

 of the body-cavity of the host ; the young become free, and the re- 

 mains of the body of the mother probably disappear by dissolution 

 and resorption 2 . In this case the remains of the mother animal seem 

 to be, to some extent, consumed by the embryos, a process which 

 sometimes, although very rarely, happens elsewhere. We can 

 scarcely consider this as a primitive arrangement, or look upon 

 it as a proof that ' reproduction ' has a necessarily fatal effect upon 

 the Polyplastid organism. 



In the male, the mass of spermatozoa does not swell out the 

 body to such an extent that its walls must give way and thus 

 permit an exit, but the large ectoderm cells atrophy spontaneously 

 at the time of maturity, and as they fall off, exit is given to the 

 spermatozoa here and there. In this instance also the dissolution 

 of the body is not a consequence of reproduction, but reproduction can 

 only take place when the dissolution of the body has preceded it ! 



1 I- c., p. 37- 



2 Julin does not enter into further details on this point, and it is not quite clear at 

 what precise time the cells of the ectoderm atrophy ; but this is irrelevant to the 

 origin of death, since the granular mass surrounding the egg-cells at any rate belongs 

 to the soma of the mother. 



