464 WoopsurRN: EMBRYOLOGY OF REBOULIA HEMISPHERICA 
LITERATURE CITED 
1. Black, Caroline A. The morphology of Riccia Frostii Aust. Ann. 
Bot. 27: 511-532. pl. 37, 38. 1912. 
2. Cavers, F. Contributions to the biology of the Hepaticae. Part > 
I.—Targionia, Reboulia, Preissia, Monoclea. Leeds and London. 
March, 1904. 
3. Garber, J. F. The life history of Ricciocarpus natans. Bot. Gaz. 
37: 161-177. pl. 9, 10 +f. I-g. 1904. 
4. Meyer, K. Untersuchungen iiber den Sporophyt der Lebermoose. 
Entwickelungsgeschichte des Sporogon der Corsinia marchantioides. 
ull. Soc. Imp. Nat. Moscou 1911: 263-286. gh. at + fi 4-22: 
1912. 
Explanation of plate 19 
The figures were drawn by Miss Mary C. Blair. 
Fic. 1. Early stage of fusion of the egg and sperm nuclei, X 1775. 
Fic. 2. Telophase of first division of zygote, X 565. 
Fic. 3. First divisio& of zygote completed; hypobasal cell ‘‘a,’’ and epibasal 
cell ““b” in prophase of subsequent division, x 
Fic. 4. Division of epibasal cell completed, sliewne tier of three cells, X 565- 
Fic. 5. Young embryo 0 consisting of tier of four cells, X 565 
Fic. 6. Hypobasal cell divided longitudinally; cell next above in process of 
longitudinal division, x 505 
F Young embryo itt wedge-shaped apical cell, K 735. 
Fic. 8. Young embryo with both basal and apical cells triangular in shape, 
FiG.0; a older than in any of the preceding figures, with wedge-shaped 
aye cell <5 
Fic. 10. . more advanced embryo than in Fic. 9, showing both apical 
and basal cells triangular in outline, X 565. 
1G. 11. Embryo showing early differentiation of foot “a,” seta “‘b,” and 
capsule ‘‘c,” X 565. / 

