STUDIES ON TWO ABERRANT CTENOPHORES, 

 CCELOPLANA AND GASTRODES 



By • 



Taku Komai. 



CONTENTS. P,„, 



INTRODUCTORY ^ 



STRUCTURE AND DEVELOPMENT OF COELOPLANA. 



Historical remarks '^ 



Material and methods 5 



External features and life-habits " 



Anatomical and histological features 9 



Epidermis ^^ 



Aboral sense-organ '4 



Tentacular apparatus ^7 



Gastro- vascular system 24 



Gonads 3^ 



Body-parenchyme 4^ 



Development 45 



Egg 45 



Segmentation 47 



Gastrulation '49 



Cydippid larva 5^ 



Metamorphosis 5^ 



Systematic position 01 



Summary "9 



GASTRODES PARASITICUM KOROTNEFF. 



Historical remarks 73 



Material and methods 73 



External features 74 



Anatomical and histological features 7° 



Epidermis 7° 



Aboral sense-organ 7" 



Tentacular apparatus 79 



Gastro- vascular system 79 



Gonad ^^ 



Body-parenchyme °4 



T)evelopmental cycle "4 



Systematic position °5 



Summary "7 



INTERRATIONSHIP OF THE MEMBERS OF THE ORDER PLATYCTENEA ; 



AFFINITY OF PLATYCTENEA TO OTHER ORDERS OF CTENOPHOSA .... 89 



DIAGNOSIS OF ALL KNOWN S1M':CIES OF PLATYCTENEA 92 



LllERATURE 94 



EXPLANATION OF PLATES 1-9 9^ 



//JW 



