clxxxiv THE VOYAGE OF H.M.S. CHALLENGES. 



ment to the numerous communications regarding the Polycystina, which he had made 

 to the Berlin Academy since 1838, and which he had published in his Mikrogeologie 

 in 1854. It will always be the merit of this zealous and indefatigable microscopist that 

 he first called attention to the great wealth of forms existing in this class ; he separated 

 systematically about 500 species, and published drawings of about 400 ; in addition 

 to which he was the first to lay stress upon the great chorological and geological 

 importance of the Radiolaria. 



With these systematic and descriptive, chorological and palseontological works, how- 

 ever, which relate exclusively to the Polycystina, the merits of the famous naturalist 

 of Berlin are exhausted as regards this class of animals. Of the organisation of the 

 Radiolaria, Gottfried Ehrenberg remained entirely ignorant up till his death in 1876. 

 All that a number of famous naturalists had observed during a quarter of a century as 

 to the structure and life-history of the Radiolaria, all the important discoveries of 

 Huxley (1851), Johannes Miiller (1858), Claparede (1858), CienkowsM (1871), and 

 many others (L. N. 122), and all that I had published in my Monograph (1862) on 

 the basis of three years' study of their anatomy and physiology all this Ehrenberg 

 ignored, or rather, he regarded it all as worthless rubbish of science, as a chaos of devious 

 errors, resting upon incomplete observations and false conclusions. His strange 

 " special considerations regarding the Polycystina " (L. N. 24, pp. 339346) and the 

 general " concluding remarks " (L. N. 25, pp. 146147) leave no room for doubt on 

 this point. Ehrenberg indeed doubted to the last whether any observer had seen 

 living Radiolaria at all (L. N. 25, p. 108). 



The invincible obstinacy with which Ehrenberg maintained his preconceived opinion 

 of the high organisation of the Radiolaria, and entirely ignored the contrary observations 

 of other naturalists, is explained by the consistency with which he held to the end the 

 " principle peculiar to himself of the universally equal development of the animal king- 

 dom" (L. N. 16, p. 7). From the complicated arrangement of their siliceous shells he 

 concluded that the animals inhabiting them must possess a structure correspondingly 

 complex, and nearly related to that of the Echinodermata (Holothuria). Like all other 

 animals the Radiolaria must possess systems of organs for locomotion, sensation, 

 nutrition, circulation, and reproduction. Whilst Ehrenberg originally interpreted the 

 Polycystina as siliceous Infusoria polygastrica, and regarded them as compound Arcel- 

 lina, he afterwards classed them sometimes with the Echinodermata (Holothuria), 

 sometimes with the Bryozoa, sometimes with the Oscillaria (see L. N. 41, p. 336). 

 Although a decided opponent of the cell-theory he called them " multicellular animal- 

 cules " (Polycystina), interpreting the pores of the siliceous shell as cells. To-day the 

 opposite term (Monocystina) might be adopted to express their unicellular organisation. 

 It was a remarkable irony of fate that in the self-same year (1838) in which Schwann 

 of Berlin made by his foundation of the cell theory the greatest advance in the whole 



