EXPLANATION OF PLATE 18 

 Noctiluca scintillans (Macartney) 



1. Dorsal view showing apical trough. After Allman (1872, pi. 18, fig. 1). 

 X 125. 



2. Lateral view from the left side showing the deep oral pouch. Modified 

 after Allman (1872, pi. 18, fig. 2). x 125. 



3. Posteroventral view showing sulcus, girdle, undulating membrane or tooth, 

 flagellum and tentacle. The anterior lip is at or near the upper margin of the 

 figure. Modified slightly after Kobin (1878, pi. 36, fig. 4). x 100. 



4a, 46. Zoospores. After Cienkowsky (1873, pi. 6, figs. 38, 42). x 500. 



5. Noctiluca in chain at mitosis showing girdle in the anterior schizont. After 

 Eobin (1878, pi. 41, fig. 24). x 125. 



6. Midventral view showing sulcus, rudimentary girdle, transverse flagellum 

 or tooth, longitudinal flagellum and tentacle. Modified after Webb (1855, pi. 6, 

 fig. 7). Magnification not given. 



Abbreviations 

 ant. I., anterior lip. 

 ap. tr., apical trough. 

 git., girdle. 



long. /?., longitudinal flagellum. 

 o. p., oral pouch. 

 t., tooth or transverse flagellum. 

 tent., tentacle. 



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