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a curious lobed cylindrical micropylar beak, pointing into 
the cavity between itself and the sclerotesta. 
The nucellus is fused to halfway its height with the 
endotesta and is covered in its upper free part with a 
well defined epidermis and cuticula, except in its apex 
above the embryosac, where a way of communication 
must be left between the latter and the pollenchamber, 
lying above in the endotesta. 
This case is a very remarkable one, for as far as we 
know amongst the Pteridosperms, the nucellus is always 
provided in its apical region with a beak in which the 
pollenchamber, whereas the endotesta is entirely concres- 
cent with the stony coat and covers the innerside of the 
micropylar tube. Here the endotesta has the function, 
otherwise performed by the nucellus itself to cover the 
thin nucellar tissue and to receive and to preserve the 
pollen by the formation of a pollenchamber. 
To be sure of the origin and nature of the different 
layers, and in order to examine whether it is possible that 
the endotesta should be an original free envelope, like an 
inner integument, | investigated the presence of cuticulae. 
For if two layers, though concrescent, are lined by a 
conspicuous cuticula, their origin must have been separate, 
and when no cuticula is to be seen, it may be possible 
that both layers are formed by the division of a single one. 
Cuticulae are best indicated by the reaction of van 
Wisselingh (173) À microscopical preparate covered 
by a cover is heated with nitric acid and potassium chlorate, 
by which the cuticulae become more and more visible 
and the cellulose and the lignified cell-walls become trans- 
lucent. To distingiush the cuticulae from the adjacent cell- 
layers Î used potassium iodide-iodine and sulphuric acid, 
after having washed the preparate with water. 
Now I could observe a cuticular-lining on the places 
which I have indicated for Torreya in fig. 9. Below the 
