Phylogeny of Animals 



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Fig. 21. — Relation of Rotifera to Annelida, a, simple Rotifer; h, young or 

 trochophore stage of Annelid; c, trocliophore stage of Polygordius: d, seg- 

 mented Rotifer NoLommala; e, polytrochal larva of the annelid Ophryolrocha; 

 f, polytrochal stage of Polygordius; g, compounded rotiferan diagram of Alberlia- 

 Taphrocarnpa; h, embryonic stage of Aeolosoma; i, third stage of Folyjordius. 



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