4o8 



BOTANICAL GAZETTE 



[DECEMBER 



cupule is less than the transverse diameter, as shown by figs. 12 and 

 1 j, which represent respectively longitudinal and transverse sections 

 through cupules of about the same age. 



Fig. 13. — Transverse section of a Fig. 14. — Origin of cupule of Lunu- 



cupule about the same age as fig. 12. laria; p, gemmiparous cells elongated and 



dividing; rim (w) developed only on pos- 

 terior margin; /, young air chamber. 



It is not necessary to follow the history of the cupule further, for 

 it is a familiar object in all laboratories of instruction and has been 

 well described. 



The cupule of Lunularia has also been investigated sufficiently 

 to show that its origin is essentially the same as that of Marchantia 

 (fig- z 4)> except that the development of the rim takes place only 

 on the posterior side of the gemmiparous region, which is also far 

 more extensive. In some cases, late in development, a slight anterior 



