Studies on the Gametophyte of Selaginella. 
BY 
D. H. CAMPBELL, 
Professor of Botany in the Stanford University , California , U.S.A . 
With Plate XIX. 
S EVERAL years ago the writer undertook the study of 
the development of the female gametophyte in Selaginella 
Kraussiana , and the results were published in brief form 1 . 
Before their publication a paper by Heinsen 2 appeared, and 
since then four other contributions have been made, by 
Arnoldi 3 , Bruchmann 4 , Fitting 5 , and Lyon 6 . Of these, the 
most important was the paper by Fitting, who corrected an 
error into which all previous investigators had fallen, the 
mistaking of the very much contracted protoplast of the 
young spore for the nucleus. Fitting also made a most 
satisfactory study of the development of the spore membranes. 
The most recent paper on the subject is by Miss Lyon. This 
is a somewhat extended study of the development of two 
native species, S. apus and 5. rupestris . The most interesting 
point recorded by Miss Lyon is the retention of the macro- 
1 Structure and Development of the Mosses and Ferns, pp. 485-504, 1895. 
2 Die Macrosporen und das weibliche Prothallium von Selaginella, Flora, 78, 
1894. 
3 Die Entwickelung des weiblichen Yorkeims bei den heterosporen Lyco- 
podiaceen. Bot. Zeit. 54, 1896. 
4 Untersuchungen iiber Selaginella spinulosa. Gotha, 1897. 
5 Flora, 1900. 
6 A Study of the Sporangia and Gametophytes of Selaginella apus and Sela- 
ginella rupestris . Bot. Gazette, xxxii, August-September, 1901. 
[Annals of Botany, Vol. XVI. No. LXIII. September, 1902.] 
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