BRIEF NOTES ON SPIROCH^TA ANODONT.E KEYSSELITZ. 393 



EXPLANATION OF PLATE 15, 



Illustrating- Dr. W. Cecil Bosanquet's paper on " Brief Notes 

 on the Structure and Development of Spirocliteta 

 anodontae Keysselitz/' 



[All the figures, except Figs. 1 and 11, are from specimens fixed in 

 osmic vapour and stained with thionin, and all are drawn at a uniform 

 magnification of 2000.] 



Fig. 1. — Spirochasta anodonta?. showing so-called undulating mem- 

 brane. From a film dried in the air and stained with iron-ha}matoxylin. 

 Fig. 2. — Sj). anodonta? — long thin specimen from crystalline style. 

 Fig. 3. — Same. Long thick specimen. 

 Fig. 4. — Same. Short thick specimen. 

 Fig. 5. — Same. Short thin specimen. ' 

 Fig. G. — Same, showing splitting of {•') sheath. 



Fig. 7. — Same. Slender specimen showing uniformity of structure 

 and absence of *■ undulating membrane," like a bacterium. 



Fig. 8. — Same. Short specimen with pointed ends. 



Fig. 9. — Same. Longer specimen with pointed ends and somewhat 

 stiff cui'ls (not well shown in the figure). 



Fig. 10. — Same. Short thin sj)ecimen with ajiparent undulating 

 membrane. 



Fig. 11. — CI. h, c, stages in apparent longitudinal division of Sji. 

 anodonta; (diagrammatic). 



Figs. 12, 13. — Stages in " incurvation" (H) of Sp. anodonta?. 



Figs. 14, 15. — Complete incurvation (!■') and subsequent transverse 

 division. 



Figs. 16, 17, 18. — Sp. anodonta?, from the alimentary canal of the 

 mussel, showing plasmolysis (?). 



Figs. 19, 20, 21, 22. — Apparent developmetit of sjjirocha-tes into 

 coccoid bodies. From a preparation of crystalline style dissolved in 

 water and kept for forty-eight hours. 



Fig. 23. — Spirochgete from water in which mussels had Ijeen kept, for 

 comparison of structure with figs. 24 a. h. showing spirilla from same 

 water. 



