Betters: OBSERVATIONS ON TKICHOGLOiA LUBRICA. 21 



Explanation of Plates. 



The figures on Plate V. are from photographs and photomicrographs, 

 those in Plate VI. are from drawings made with the Abbe camera. 



i. Entire plant of Trichoglcea lubrica (Harv.) J. Ag., about three 

 fourths natural size. After photograph by C. J. Hibbard. 



2. The growing point of a branch of the frond, x 120. 



3. Detail from somewhat older portion of the frond, X 65. p, pri- 

 mary medullary filament; 5, one of the smaller medullary filaments; 

 .>-', a vounger filament of the same type; c, young cystocarp. 



4 A single mature cortical branch system, x 25. 



5. An antheridial cortical branch system, x So. ft, primary med- 

 ullary filament ; s, one of the smaller medullary filaments ; s', a younger 

 filament of the same type; c, young cystocarp. 



6. Cross-section of mature portion of frond, x 32. ' Part of the 

 calcareous incrustation has been removed with hydrochloric acid. /, 

 remains of the deposit of lime. 



7. Detail from cross-section of* medullary region of mature frond 

 showing the two kinds of medullary filaments, X 116. 



S. Detail of antheridial cortical filament, X 438. 



9-16. Stages in the development of the protocarp and cystocarp. 

 a, auxiliary stalk-cell; s, stalk-cell; c, fertile portion of carpogonial 

 cell after the cutting off of the stalk-cell. 



9. Young procarp, x 600. 



10. Procarp with the trichogyne about half developed, X 475- 



11. Mature and fecundated procarp, X 475. 



12. Carpogonial branch after the first division of the carpogonial 

 cell, x 600. 



13. A somewhat later stage in the development of the cystocarp, 

 X 700. 



The distal segment of the carpogonial cell has divided a second 

 time transversely, and the segments are dividing longitudinally. The 

 growth of pericarp filaments has begun. 



14. A developing cystocarp, slightly later stage than Fig. ij, in 

 position among the surrounding cortical filaments, X 400. 



15. Young cystocarp with the developing gonimoblast, x 475- 



16. Mature cystocarp, X 43S. From section 6.66 mic. thick. 



17. Detail of developing gonimoblast, X 640. 



