UNIVERSITY OF CALIFORNIA PUBLICATIONS 



IN 



ZOOLOGY 



Vol. 19, No. 10, pp. 317-334, plate 18, 2 figures in text February 13, 1920 



A NEW MORPHOLOGICAL INTERPRETATION 



OF THE STRUCTURE OP NOCTILUCA, AND 



ITS BEARING ON THE STATUS OF THE 



CYSTOFLAGELLATA (HAECKEL) ^S^S^BSS!^ 



MAR20)m 



CHARLES A. KOFOID V , 



The purpose of this paper is to set forth certain observations on the 

 structure of Noctiluca, to call attention to the bearing of some recently 

 discovered types of Gymnodiniidae upon the relationships of Noctiluca, 

 and to present a new interpretation of the orientation and morphology 

 of this well-known organism. This interpretation indicates that the 

 allocation of Noctiluca as the generic type of a separate order of the 

 Alastigophora, namely the Cystoflagellata Haeckel (1873). is no longer 

 justifiable by the canons of comparative morphology, and harmonizes 

 its structures with those of the tentaculate dinoflagellata. 



In the recent fourth edition of his Lehrbuch der Protoeoenkunde, 

 Doflein (1916, p. 663) places the Cystoflagellata as the fifth and last, 

 and presumably the highest order of the Zoomastigina. quite remote 

 from Dinoflagellata. with this qualifying statement : 



"Die systematische Stellung dieser Ordnung ist noch nicht klar erkannt. 

 Man hat vielfach, auch wegen der ausserlichen Aehnlichkeit der Schwarmer 

 von Noctiluca rait solchen an die Verwandsehaft mit Dinoflagellaten gedacht. 

 Vorlaufig liegen keine einleuchtenden Beweise fur solchen Annahme vor. Doch- 

 miissen wir manche der Charactere der Cystoflagellaten fiir Anpassungen an die 

 planktonische Lebensweise halten und eine niihere Erbrterung der Verwand- 

 schaftsverhaltnisse wird erst mbglich sein, wenn Bau und Fortpflanzungsweise 

 der hierher gereehneten Formen genauer erforseht sein wird. ' ' 



Data of a comparative and interpretative nature we here offer to 

 elucidate this relationship of Noctiluca to the Dinoflagellata. 



