1920] Kofoid: New Interpretation of the Structuri of NoctUuca 32] 



. B— I. Evolution of tentacle in the Gymnodinioidae. 



Fig. B. Oxyrrhis marina Dujardin after Senn (1911, pi. 30, fig. 9), showing 

 tentacular lobe adjacent to bases of the flagella in the generalized sulcal area. 



Fig. < '. C iimiiiiiliiiium sachariasi Lemm. showing temporary pseudopodia 

 emerging from the sulcus. After Zacharias (1S99, tig. 4). x 500. 



Fig. D. Gymnodinium pseudonoctiluca (Pouchet) showing temporary! f) 

 tentacle and smaller pseudopodia arising from margin of the sulcus. After 

 Pouchet (1885, pi. 4, fig. 2, right). 



Fig. E. Cochlodinium minium Kofoid and Swezy MSS, showing protuberant 

 antapex adjacent to sulcus, x 500. 



Fig. F. Pouchetia maculata Kofoid and Swezy MSS, showing short mobile 

 extension at the side of the sulcus, x 500. 



Fig. G. Proterythropsis crassicaudata gen. nov., sp. now, Kofoid and Swezy 

 .MSS, showing protuberant, pendant and mobile tentacle with both flagella 

 present. X 500. 



Fig. H. Pavillardia tentaculifera gen. nov., sp. nov., Kofoid and Swezy MSS, 

 showing normal sulcus and girdle with the two flagella and a tentacle at the 

 posterior end of the girdle as in NoctUuca. 



Fig. I. Erythropsis extrudens Kofoid and Swezy MSS, showing stout, very 

 active tentacle or prod, protruding from the lower end of the sulcus, which is trans- 

 formed into the tentacular chamber or recess. No longitudinal flagellum figured. 



