XLVIIl] 



PITYOSTROBUS 



391 



ovule shown in fig. 784, A, the contracted nucellus, n, forms a 

 cylindrical column which presents a misleading resemblance to the 



Fig. 783. PUyostrohus (Pinites) macrocephalus. (After Gardner; nat. size.) 



Fig. 784. Piiyostrobus (Pinilea) macrocephalus. A, section of an ovule; n, nucellus. 

 B, longitudinal section of part of the cone. (From sections in the British 

 Museum; B, slightly reduced.) 



prothallus tent-pole of Ginkgo ovules: at its blunt apex are two 

 winged pollen-grains. Prothallus-tissue is also represented. 



Carriithers compared the species with Pinus Pinaster but the 



