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University of Califorina Publications in Zoology [Vol. 16 



In figure 3 the division of the parabasal body is shown, and again, 

 as in the preceding form, there seems to be no necessary connection 

 between it and the figure following. To call the structure in figures 



Figs. 1-3. Trypanosoma noctuae (Halteridi-um noctuae), from Minchin (1912, 

 figs. 30a-b-e) after Sehaudinn (1904, figs. Ic-d-e). Fig. 1. Nucleus of the 

 "ookinete" is dividing into two unequal halves: the divided centriole is con- 

 nected by a " centrodesmose. " Fig. 2. Division of the nucleus completed; 

 " centrodesmose" uniting the two daughter nuclei. Fig. 3. The smaller 

 nucleus is dividing to furnish a third nucleus. The second nucleus probably 

 represents pigment granules common in this species. 



Figs. 4-6. Trypanosoma noctuae, from Minchin (1912, figs. 30d-e-f) after 

 Sehaudinn (1904, figs. If-g-h). Fig. 4(?). The third nucleus is dividing to 

 furnish a proximal and a distal centriole. Fig. 5. Further division of the 

 third nucleus, with the fibrils of the achromatic spindle forming the myonemes, 

 the "centrodesmose" the flagellum. Fig. 6. Fully developed trpanosome. The 

 "centrodesmose" represents the rhizoplast joining the nucleus and the related 



Abbreviations: bg., smaller nucleus dividing to form a third nucleus; bg.,^ 

 bg.,' prciimal and distal eentrioles formed by division of the third nucleus, 

 bg.^ becomes the blepharoplast of flagellum; my., myonemes formed by achro- 

 matic spindle; JV., trophonucleus; «., "kinetonueleus; " P., pigment granules. 



4 and 5 a spindle is quite conjectural, though it may represent a simple 

 outgrowth of the flagellum and membrane. The figures throughout 

 seem, in the light of our fuller knowledge of the structure of haerao- 



