^/^^_ 



^°^§Wy in ace. 



Ti which 

 )leof 



we 



giving bici 



J to the influfK 



■cumstance 



s 



) r 



ut although 



recorded, tk;: 

 the egg of one: 

 : Rotifers, in*: 



of developm;' 



I 



I 



■ely unfavoofrj 

 filiated Infe' 



^ 



jnces it ma)'?' 



i. l 



vcn 



resolve i*^'- 

 thousafl'is of " 



I 



I 



©ay 



for ii' 



taJtS' 



\ 



un 



der 



less 



)e 



comes 

 isible u' 



re 





odes 



oft^' 



CHAPTER XXII. 



TRANSFORMATIONS OF CILIATED INFUSORIA : MODES OF ORIGIN 



OF ROTIFERS, TARDIGRADES, AND NEMATOIDS. 



Convertibility of Lower Forms of Life. Similar Convertibility of 

 Ciliated Infusoria. Vorticella into Oxytricha. Oxytricha into 

 Trichoda. Mr. Carter's Observations. Recent Confirmation of 

 these neglected views. Other Developmental Metamorphoses. 

 General Conclusions concerning Ciliated Infusoria. Their ultimate 



Transformations. 

 Origin of Rotifers. Dr. Gros' Observations. Confirmed by Trans- 

 formation of Vorticella into Diglena. Conversion of Actinophrys 



into embryo of Rotifer. Fate of other 



large 



specimens of 



Actinophrys. Direct Origin of Rotifers from Vegetal Vesicles. 

 Conversion of ' winter-spore ' of Volvox into Philodinian Rotifer. 

 Similar Transformations of Euglense or of Moss-sporangia into 

 other Rotifers. Author's Observations on so-called 'winter-eggs' of 

 Hydatina. Their Mode of Formation from aggregations of Chloro- 

 coccus Vesicles and of Euglence. Instances of Synthetic Hetero- 

 genesis. Reproduction amongst Rotifers. Transformation of Acti- 

 nophrys into Planariole, and of Planariole into Tardigrade. Similar 



Transformations of Small Rotifers into 

 Nematoids.^ Direct Origin of Tardigrades and Nematoids from 

 Euglenoe. Indubitable Nature of these Changes. Author's Obser- 

 vations on Origin of Nematoids. Conversion of ' resting-spore ' of 

 Vaucheria into an embryo Diplogaster. Inexplicable Facts. 

 New Views harmonious with previous Observations. Universal 

 Distribution of Rotifers, Tardigrades, and Nematoids. Failure 

 of the Panspermic Hypothesis. Heterogenetic Origin of other 

 Higher Forms. Unsolved Problems. 



Origin of Nematoids. 



'T^HE facts hitherto recorded concerning the modes 



-A- of origin of Ciliated Infusoria are of such a 



nature as to lead us to expect that these varied forms 



