33 ° 
Hill and de Fraine.—On the 
remark upon the presence of four vascular bundles in the apex of the 
cotyledons of Ginkgo . The author cited does comment upon this feature, 
and in making this correction we desire to express our regret to Dr. Sprecher 
for the misrepresentation. 
SUMMARY. 
Cotyledons. 
1. The plants examined, viz. Ephedra distachya, E. fragilis, E. campy - 
lopodia, E. altissima , Welwiischia mirabilis , Gnetum Gnemon , G. scandens , 
and G. molnccense , have dicotyledonous and epigeal seedlings. 
2. The cotyledons of Ephedra are linear in shape ; at first they are 
small, but with increasing age they elongate greatly. The seed-leaves 
of Welwitschia are large and leaf-like, and persist relatively for a long 
time ; those of Gnetum to begin with are scale-like and their growth 
is slow, finally they attain a large size, and closely resemble the foliage 
leaves. 
3. In all cases a short cotyledonary tube is formed. 
4. The number of cotyledonary bundles varies; in all the Ephedras 
examined there are two traces in each seed-leaf; in Welwitschia there are 
in the base of each seed-leaf four strands arranged in two pairs ; in Gnetum 
four or five bundles occur in the lowest region of the cotyledons. 
5. The seed-leaf-traces are endarch and collateral in structure. 
Hypocotyl. 
6. The upper part of the hypocotyledonary axis shows a stem-like 
structure ; the chief bundles, in the material examined, are those derived 
from the cotyledons; of these strands there are four in Ephedra , eight 
or less in Welwitschia which quickly become reduced to four, and a variable 
number, about twelve or fifteen, occur throughout the greater length of 
the hypocotyl in Gnetum . 
7. In Gnetum and Welwitschia a parenchymatous outgrowth occurs at 
the base of the hypocotyl; this is the foot or sucker, which is rod-like in 
the former plant and spade-like in Welwitschia. The foot functions as an 
organ of absorption, and remains embedded in the prothallus. The sucker 
in Welwitschia has no vascular supply, but in Gnetum the bundles in the 
foot are numerous and well differentiated. 
A foot has not been observed in Ephedra. 
This structure is not considered to have any phylogenetic importance. 
8. Short tracheides, closely resembling the transfusion tracheides 
obtaining in the cotyledons of other Gymnosperms, occur in all the plants 
examined in the region of the insertion of the plumular bundles on to the 
cotyledonary traces. These tracheides form a bridge between the corre¬ 
sponding bundles of the seed-leaves. 
