THE EMBRYO AND YOUNG SPOROPHYTE OF 
ANGIOPTERIS AND KAULFUSSIA. 
BY 
DOUGLAS HOUGHTON CAMPBELL. 
(With Plates VI and VII), 
The peculiar order of ferns, the Marattiales, has a special 
interest because they are probably more nearly related to the 
ferns and Pteridosperms of the Palaeozoic than are any other 
living plants. 
The existing Marattiales comprise only about thirty species, 
most of which are natives of the mountain regions of the 
Tropics, although a very small number occur in the sub-tropical 
q regions of Australasia and Eastern Asia. Of the five living 
_ genera, three, all belonging to the old world, are generally 
_ considered to be monotypic, although sometimes they are divided 
7 into several species. These monotypic genera are Angiopteris, 
1 Kaulfussia and Archangiopteris. Danaea, with about fifteen 
4 species, is confined to the Neotropical regions, while Marattia, 
' with about a dozen species, is pretty well distributed throughout 
_ the tropics of both the Old and the New World. As the Ma- 
_Yattiaceae are rare in cultivation, and the development of the 
prothallium is very slow, they offer special difficulties in the 
Study of the development of the gametophyte and embryo, 
and this explains the small number of investigations that have 
q been made upon them. There is still much to be learned, 
_ especially as to the development of the embryo and the young 
