81 HOFMEISTER, ON 



of the spores of a leafy Jungermannia, /. crenulata* 

 That account does not extend beyond the formation of a 

 short filament from the inner spore-cell. After Gottsche's 

 observations no notices of the germination of Jungerman- 

 niae appeared until my own, mentioned above. At a later 

 period Gronlandf published his investigations of the germi- 

 nation of the leafy Jungermanniae. He showed that the 

 formation of the long, cylindrical tube discovered by 

 Gottsche in the germination of Blasia was suppressed in 

 cases where the spores were very thinly sown ; that under 

 these circumstances the spore immediately assumes the form 

 of a cellular body, similar to that which, when the spores 

 are sown thickly, originates in the end of each tube, j He 

 pointed out, moreover, the occasional ramification of the pro- 

 thallium of leafy Jungermanniae, and extended the obser- 

 vation to some species hitherto not investigated or only 

 imperfectly so Sarcoscyphus Funkii, J. crenulata, and 

 Alicularia scalaris, the development of which in other 

 respects exhibits nothing peculiar. 



The first important observations as to the mode of growth 

 and cell-multiplication of the ends of the stems of Junger- 

 manniae are those of Nageli. || He pointed out the mode 

 in which the terminal cell of the leafy axis of Metzgeria fur- 

 cata divides by alternating septa, directed obliquely right 

 and left perpendicular to the surface of the stem, and the 

 way in which the cells of the second degree thus formed 

 produce, by continued bisection, the entire mass of cellular 

 tissue of the flat stem. He showed further that the growth 

 of the stem which^[ is developed from the gemmae of J. ex- 

 secta, and that of the end of the stem of /. tricliophylla** 

 was produced by continual division of a single apical cell, 

 by means of oblique septa, of the same or a like inclination, 

 but differing in position. I have not obtained from my 

 own observations of the leafy Jungermanniae any ground of 



* l. c, pp. 387, 391. 

 f 'Ann. d. Sc.,' iv ser., t. i, p. 1. 

 t I. c, p. 20. 

 I. c, p. 16. 



j ' Zeitschrift f. wiss. Bot.'H. 2 Zurich, 1843, 138. 

 ^j /. c, p. 166. 

 ** /. c, p. 172. 



