G. R. Wieland — American Fossil Cycads. 



389 



portance present themselves for mention. A number of species 

 bear fruits of the type represented in the well-known figure of 

 C. etrusca given by Capellini and Solms-Laubach (Plate IY). 10 

 These heart-shaped fruits have very closely set, rodlike seeds 

 arranged prismatically on a short, fleshy axis, traversed by nu- 

 merous gum ducts and usually devoid of the regularly arranged 

 seed sterns and interseminal scales characterizing C. (Bennett- 

 ites) Gibsonianus, O. Morierie, and G. Wielandi. Should 

 there prove to be no intervening forms and no connection 

 during developmental stages, this must be finally regarded as 

 a strong generic difference. One of the Yale specimens not 

 yet fully studied, but nearly related to C. etrusca, as far as 

 may be judged from general features, displays seeds with well- 

 marked cotyledons, as represented in figure 7, Plate IX. 

 Another closely related trunk, of which the female form also 

 is known, shows well-preserved male cones of essentially the 

 same character as those described in Part I of these contribu- 

 tions. Pollen grains, both distended and dessicated, and repre- 

 sented in figures 9-16, are present in rare preservation. They 

 are so like the dissociated pollen figured by Capellini and 

 Solms-Laubach 10 in their description of G. etrusca that figures 

 17-20 in the text are introduced for comparison, as well as 

 pollen from the living cycad Geratozamia, figures 3-8. That 

 these fossil bodies represent characteristic cycad pollen is be- 

 yond all question. Sections of the cycadeoidean cone from 

 which the pollen of figures 9-16 was derived are given in 

 figures 17 and 18, Plate X. 



Figures 3-8. — Ceratozamia longifolia, Miquel; pollen grains. (After Juranyi.) 

 x 610. 

 3, mature pollen in dry condition; 4, 5, the same swollen in water; 6-8, the 

 respective transverse sections, or end views. 

 Figures 9-16. — Cycadeoidea, sp., Black Hills; pollen grains, x 250. 



9, 10, 13-15, more or less dessicated grains: 11, 12, 16, normal forms. 

 Figures 17-20. — Cycadeoidea etrusca, Capellini and Solms-Laubach; isolated and 

 dried pollen grains. (After Capellini and Solms-Laubach). 



