of the Anatomy of the Genus Selaginelia , Spr. 137 
21. Vladescu. Communications prdliminaires sur la structure de la 
tige des Selaginelles. Jour. d. Bot., 1889. 
22. Dangeard. Essai sur Tanatomie des Cryptogames vasculaires. 
Le Botaniste , Vol. I. 1889. 
23 . Wojinowxc. Beitrage zur Morphologic, Anatomie und Biologie der 
Selaginelia lepidophylla , Spr. Inaug. Biss. Breslau, 1890. 
24 . Strasburger. Uber den Bau und die Verrichtungen der Leitungs- 
bahnen in den Pflanzen. Histolog. Beitr. III. 1891. 
25 . Van Tieghem. Traite de Botanique. 2nd Ed. Paris, 1892. 
26 . ,, Pdricycle et Peridesme. Jour. d. Bot., 1890. 
27 . Bower. On the structure of Lepidostrobus Brownii, Sch. Ann. 
Bot., Vol. VII, 1893. 
28 . Harvey Gibson. On the siliceous deposit in certain species of 
Selaginelia. Ann. Bot., Vol. VII, 1893. 
29 . Belajeff. Antheridien u. Spermatozoiden der heterosporen Lyco- 
podiaceen. Bot. Zeit ., 1885. 
Historical Summary of Researches on the 
Anatomy of the Stem. 
A considerable number of papers have been published on 
the anatomy of Selaginelia ; but these, as has been already 
stated, deal with only a few species. Moreover, the more 
important of these monographs treat either of the development 
of the vegetative organs, or of the special anatomy and 
development of the sporangia and their contents. Quite 
recently the structure of the leaf has received some attention 
from Erikson(6). 
Spring s classic monograph ( 5 ) is so well known to all 
students of the Vascular Cryptogams that I need not do 
more than briefly refer to that part of his work which deals 
with the subject of the present paper. After an exhaustive 
discussion of the external morphology of 209 species of 
Selaginelia , Spring gives an organographical summary of the 
family of the Lycopodiaceae, in which Selaginelia is compared 
with the other genera which he includes under the group. 
Amongst other points he insists on the importance of con- 
sidering the sectional outline of the stem in the determination 
L 
