150 G. B. Wieland — American Fossil Cycads. 



Fig. 8. 



X/5. 



T..I3I. S.766. 



Fig. 8. Cycadeoidea Macbridei (?). 



Part of a somewhat oblique section through a strohilus of Y. T. 131 

 cutting nine seeds at angles varying from nearly transverse (e, e2) to tan- 

 gential longitudinal (e5 and n) and illustrating the embryos and embryo 

 bundle system. The position of the several sections is quite obvious: — e 

 with its embryo is cut high up just where the cotyledonary node gives off 

 the two supply bundles for the cotyledons ; e2 passes lower but is still rather 

 near the cotyledonary plate since neither radical nor sinus between the 

 lamina appears ; while in the seed beloiv e% the upper part of the pedicel is 

 cut and the forking of the bundles in the tips of the cotyledons is evident ; 

 e5 and the seed alongside it are decidedly tangential, though in each both 

 cotyledons appear. 



In each of the seeds e-eS a lateral deeply stained mass of endosperm (?) 

 appears beside the embryo. In three of the seeds the embryo fails wholly 

 of preservation, but the nucellar sacks (n, n, n) are wholly distinct, collapse 

 and folding of this sack as here so clearly to be seen being of much interest 

 in connection with various forms of nucellar sack rupture in many Cyca- 

 deoidea seeds. 



