CERATOMYXA ACADIENSIS. 



EXPLANATION OF PLATES. 



All the figures in Plates I to III were drawn from smear preparations with 

 the aid of an Abbe camera lucida, a Zeiss apochromatic 2 mm. oil immersion 

 objective and compensating ocular No. 18 at a magnification of 2950 diameters; 

 and are reproduced without reduction. 



PLATE I. 



Myxosporidia of Ceratomyxa acadiensis; Figures 1-4, 8 from preparations 

 of the bile of Pseudopleuronectes americanus; Figures 5-7, 9-12 from prepara- 

 tions of the bile of Urophycis chuss. Figures 1, 2, 4, 8 are from preparations 

 stained with Delafield's haematoxylin ; Figures 3, 5-7, 9-10, 17, 18 from 

 preparations stained with Giemsa's azur-eosin. 



Figure 1. Individual with a single nucleus. 



Figure 2. Individual containing a large vegetative and a small propagative 

 nucleus. 



Individual with two large vegetative and two smaller propaga- 

 tive nuclei. 



A myxosporidium containing four nuclei,— Figure 4, showing 

 one large vegetative nucleus and two small propagative 

 nuclei; Figure 5, at a different level, showing one large 

 vegetative nucleus. 



An individual containing a larger vegetative nucleus, stained 

 red, and a smaller propagative nucleus, stained dark mauve. 



Myxosporidium as in Figure 6. 



An individual with one large vegetative nucleus and two small, 

 more deeply stained, propagative nuclei. 



A myxosporidium containing two larger more faintly staining 

 vegetative nuclei and two smaller more deeply staining 

 propagative nuclei each surrounded by a protoplasmic area 

 stained blue. 



Individual similar to that seen in Figure 9. Just outside one of 

 the blue protoplasmic areas can be seen a chromatin mass prob- 

 ably extruded from the propagative nucleus nearest to it. 

 Figures 11-25. The development of the sporoblast into the spore in C. 

 acadiensis from the gall bladder of Urophycis chuss. 

 Figures 11, 12, 16. Three views of a myxosporidium containing eight 

 nuclei, each surrounded by a differentiated area of protoplasm, 

 blue in the preparation. Figure 16 is the appearance at a high 

 focus showing one of the nuclei; Figure 11 at the middle 

 focus showing five of the nuclei; and Figure 12 at a low- 

 focus showing two of the nuclei. 

 Figures 13-15. Views at three levels of a myxosporidium containing 

 eleven nuclei, each with a differentiated area of protoplasm 

 around it; Figure 13 at a high focus. Figure 15 through the 

 middle and Figure 14 at a low focus. 



A myxosporidium containing twelve nuclei with their differ- 

 entiated areas of protoplasm (blue in the preparation) arranged 

 to form a pair of sporoblasts. 



Figure 3. 

 Figures 4, 5. 



Figure 6. 



Figure 7. 



Figure 8. 



Figure 9. 



Figure 10. 



Figure 17. 



