196 



MORPHOLOGY OF GYMNOSPERMS 



material, and especially taking into account numerous abnormal 

 cases, came to the conclusion that the stalk is a shoot usually bearing 

 two rudimentary carpels (megasporophylls) which are represented 





Fig. 223. — Ginkgo biloba: part of a long branch bearing dwarf branches with 

 ovulate strobih. — After Coulter (54). 



by the two collars. The abnormal cases may be summed up as foUov/s : 

 ovules on more or less modified foliage leaves; intergrades from nor- 

 mal collars to blades bearing ovules; distinctly stalked ovules; stalks 



