56 



PRINCIPLES OF PLANT-TERATOLOGY. 



The changes clue to metamorphosis and .hermaphro- 

 ditism must be next considered. 



Cutting noticed a curious condition of affairs in 

 Marehantia palmata. In the archegoniophore there 

 was an outgrowth from the lower side of the disk or 

 cap ; the upper surface of this outgrowth was directed 

 downwards and bore antheridia, while its stalk bore 

 archegonia at the base. This case is remarkable 

 owing to the fact that a new male branch is formed 

 long after the whole inflorescence has been definitely 

 differentiated as a female one (fig. 15 a and b). 



v 



Fig. 15. — Marehantia palmata. a. Archegoniophore showing a male 

 outgTOAvth. b. Hermaphrodite branch from an archegoniophore. 

 ar. Archegonia. an. Antheridia. (After Cutting.) 



Ernst observed mixed inflorescences in the liver- 

 wort Diimortiera, both in the dioecious D. velutina and 

 the monoecious D. trichocephala, Goebel found in the 

 liverwort Preissia commutata that the abnormal andro- 

 gynous inflorescence bore antheridia on the upper 

 surface of the front side, and archegonia on the lower 

 surface at the back. He does not, however, consider 

 it a reversion to an ancestral monoecious condition. 



In the same plant Townsend found antheridia 

 present in what, from its shape, was undoubtedly an 

 archegoniophore in the first instance. 



In Physcomitrium enmj stoma each plant had three 



