284 



Alexander W. Evans, 



elaters, so that his statements about the inflorescence and elaters 

 must have been based on a misconception. 



The thahus of M. papillata is even smaller than in M. domin- 

 gensis; it is, in fact, the smallest American species known at the 



Fig. 13. Marchantia papillata Raddi 



Appendages of ventral scales and other anatomical details. A-E. 

 Appendages of ventral scales, B and C having been dissected from the 

 same thallus, x 100. F. Epidermal pore of thallus, surface view, x 225. 

 G, H. Pores in cross-section, x 225. I. Inner opening of pore, x 225. 

 J. Stalk of female receptacle, cross-section, x 40. K-M. Parts of 

 involucres, x 100. A. Brazil, G. Raddi, type. B, C, G, J, K. Paraguay, 

 B. Balansa 4006. D-F, H, I. Bolivia, R. S. Williams 2145. L, M. Peru, 

 R. Spruce, type of M. subandina. 



present time. So far as the structure of the thallus is concerned 

 the agreement with M. dom'mgensis is very close. Slime cells 

 seem to be always lacking in both species and sclerotic cells are 

 usually abundant and equally conspicuous. The appendages of 

 the median scales, moreover, are essentially the same, although 

 the marginal teeth in M. papillata exhibit a slightly wider range 



