402 West. — A Contribution to the Study of the Marattiaceae . 
Genus . 
Examined by. 
Stem-stele . 
Leaf-trace. 
Root-stele , 
Danaea 
Kuhn (43) 
+ 
Brebner (11) 
+ * 
— 
+ 
Kaulfussia 
Kuhn (42) 
- 
- 
+ 
Farmer and Hill (29) 
+ 
Campbell (20) 
+ * 
+ 
+ 
A rchangiopteris 
G Wynne- Vaughan (30) 
— 
— 
+ 
Marattia 
Russow (53) 
— 
Holle (34) 
— 
— 
+ 
Thomae (65) 
— 
KUhn (42) 
— 
— 
+ 
Farmer and Hill (29) 
+ 
Charles (23) 
+ 
+ 
Angiopteris 
Sachs (55) 
— 
— 
Holle (34) 
— 
— 
+ 
de Bary (1) 
— 
_ 
+ 
Thomae (65) 
— 
Shove (58) 
— 
+ 
Farmer and Hill (29) 
+ 
+ 
+ denotes presence of an endodermis ; — denotes absence of an endodermis : * = not recogniz- 
able in older rhizomes. 
According to Jeffrey ( 36 , p. 122), the phloeoterma ( = endodermis) of 
the Marattiaceae is characteristically present in the stem of the young 
plant even when it is absent in the adult. He adds that the primitive 
medullary strand is generally surrounded by a well-marked phloeoterma. 
Leclerc du Sablon ( 54 ) remarks, with reference to Angiopteris , that ‘ Le 
peu de nettete de l’endoderme est le caractere special ’. 
Such wide differences of opinion would suggest that in this group of 
Ferns the distribution of an endodermal layer is most erratic, and that there 
is very little constancy in the position of histologically differentiated 
endodermal cells. The present writer’s observations on Danaea spp. have 
shown that this is actually the case. When present, the endodermis 
is very conspicuous, 1 and can readily be recognized in sections stained with 
safranin and haematoxylin, especially when they are mounted in euparal. 
A very distinct endodermis surrounds the stele of the young sporophyte, 
being easily distinguished in the stem and petiole as well as in the root. 
But in older plants no general rule can be laid down as to its distribution ; 
for instance, all attempts to demonstrate its presence in the leaf-traces and 
petiole met with no success ; on the other hand, an endodermis is invariably 
found in roots of all ages. 
Occasionally an endodermal layer can be observed completely sur- 
rounding a stem-meristele (the central strand, or strands, are included in this 
category), but more frequently this layer is incomplete, or absent altogether. 
No trace of an endodermis could be demonstrated round the stem- 
meristeles of a number of sections which were carefully examined after 
treatment with concentrated H ? S 0 4 , 
1 According to Rumpf (52, p. 34 , Taf. II, Fig. 4 S), the endodermal cells of the Marattiaceae 
belong to his primary type. 
