Evidence from Protozoafis 



5579 



points out, skeletal production is no mere matter of simple secre- 

 tion, or still less of crystallization, hut of genuiiH- ortjauic <;r()wtli, 

 as a detailed study of the eomphtcd struetiirc and liist()ji:«'ncsi.s 

 of the parts shows; and by the fiirthtr l.iet tlial tlir parts i-on- 

 cerned present characteristic dirt'ercnces for the dilfi r( nl s|)fcie.s. 

 Thus in the genus Aulosphacrn to which Ix-lon^s I lie spcci«-s we 

 have taken as an example, Haeckel rccogiii/cd t\v( nty-one spe- 



— a>s'p. 



-'CIS p. 

 --c.cayx 



FIGURE 25. AULACAXTHA (aFTEK BOUOERT). 



as'p., astropyle. c.cap., central capsule, n., nucleus. 



cies. Hacker re-examined about a tliird of these and a(hled tour 

 new ones. And the specific distinctions are furnished hardly 

 in skeletal details. 



(f) Openings in the Central Capsule of the liadiohiria 



Along witb these facts of skeletal (level<)|)nieMt may Ik* 

 considered the development of the o})cMln<,rs of the central 



