xiv INVE11TEBKATA 



CHAPTER XI 

 POLYZOA 



The development of Membranipora as typo of the Polyzoa ectoprocta The Cypho 

 nautes larva and its metamorphosis Other types of larvae belonging to the 

 Polyzoa ectoprocta The formation of buds in Polyzoa ectoprocta The develop- 

 ment of Pedicellina cch'inata as a type of the Polyzoa entoprocta : its larva and its 

 peculiar metamorphosis Ectoproct and Entoproct larvae compared General con- 

 clusion as to the ancestral history of Polyzoa, Ectoprocta, and Entoprocta. Page 386 



CHAPTER XII 

 BRACHIOPODA 



The development of Terebratulina septcntrionalis as type of the Brachiopoda 

 Affinities of the Brachiopoda as indicated by their development . Page 407 



CHAPTER XIII 

 ROTIFERA 



The development of Callidina russeola as a type of the Rotifera The affinities of the 

 Rotifera . ... Page 418 



CHAPTER XIV 

 CHAETOGNATHA 



The development of Sacjitta bipunctata as a type of the Chaetognatlia The ancestry 

 of the generative organs The affinities of the Chaetognatlia . . Page 428 



CHAPTER XV 



NEMATODA 



The development of Ascaris incij/tloccphda as a type of the Nematoda Methods of 

 obtaining, rearing, and preserving the eggs The cell-lineage The diminution 

 of chromatin The formation of layers The Rhabditis larva The development 

 of T-giants and the conclusions as to the constitution of the egg-cytoplasm to be 

 deduced from them The development of doubly-fertilized eggs and their bearing 

 on the caiises of diminution of the chromation Experiments on the egg of 

 Ascaris The affinities of the Nematoda .... Page 437 



CHAPTER XVI 

 ECHINODERMATA 



The development of Asterias as a type of the Asteroidea Methods of obtaining the 

 eggs of Asterias Methods of preserving and mounting the eggs and larvae of 



