455 
Botrychium simplex , Hitchcock. 
Dr. Baas-Becking, who has been engaged recently in a study of the 
later stages of the young sporophyte, finds that B. simplex shows some 
differences in the development of the early leaves, the cotyledon varying 
somewhat in its development, but never being so reduced as in B. lunaria , 
and there is never such a series of rudimentary leaves as Bruchmann 
describes for that species. Dr. Baas-Becking suggests that possibly the 
long subterranean existence of B. lunaria in Europe may be due 
to less favourable conditions than those under which the specimens of 
B. simplex were found in Minnesota. It would be interesting to know how 
B. lunaria in the northern United States and Canada compares in this 
respect with the European specimens studied by Bruchmann. 
EXPLANATION OF FIGURES IN PLATE XVI. 
Illustrating Professor Campbell’s paper on the Gametophyte and Embryo of Botrychium 
simplex , Hitchcock. 
/ 
Fig i. Very young gametophyte of Botrychium simplex, x 50. 4, antheridia ; $ archegonia. 
Fig. 2. A somewhat older gametophyte. x 32. 
Fig. 3. Median longitudinal section of a small gametophyte. x too. x, growing-point. 
Fig. 4. Growing-point of the gametophyte. x 400. x, the apical cell. 
Fig. 5. Cross-section of the gametophyte, showing the relative position of the antheridia and 
archegonia. x 100. 
Fig. 6. Cross-section of a very small gametophyte. x 100. 
Figs. 7-9. Young antheridia. x 400. In Fig. 8, x is the apical cell of the gametophyte. 
Fig. 10. Three spermatozoids, from an open antheridium. x 900. 
Figs. 1 1— 1 3. Young archegonia. x 400. 
Fig. 14. Median section of a mature archegonium. x 400. 
Fig. 15. Venter of a mature archegonium, showing a second nucleus (?), v, perhaps repre- 
senting a ventral canal-cell ; c, lower part of neck canal-cell, x about 600. 
Fig. 16. Two views of a gametophyte with young sporophyte attached, x 5. 
Fig. 17. An older sporophyte, still attached to gametophyte, pr. x 3. 
Fig. 18. a , second leaf with rudimentary sporangiophore. x 3. b, sporangiophore. x 10. 
Fig. 19. Second leaf with relatively well developed sporangiophore. x about 10. 
