1 8 INTRODUCTION. 



attention to Gray's genera, and Dr. Carrington in 

 1870 indicated those which had a good claim for 

 adoption. Dumortier at this time, and previously, 

 had been advocating and employing a classification, 

 of which the colesule and its bracts was the chief 

 basis, but this was only partially adopted, and was 

 gradually superseded by a more natural arrange- 

 ment, to which the writings of our own Dr. R. 

 Spruce largely contributed, and which received per- 

 haps its fullest expression in his " Hepaticae Amaz- 

 onicai et Andina^ " in I884. The arrangement 

 herein adopted is based mainly upon the last-men- 

 tioned work, although for a small local flora it has 

 not been considered advisable to adopt the sub- 

 divisions of each genera, as Lejeunia. 



The primary division of the whole of the Jun- 

 gevjiianiiiacecE into two tribes, viz., the Jubulece and 

 \}cv^ JiingennanniecB seems to demand recognition. 

 And in general terms it may be indicated that the 

 JubulecB have a four-valved capsule, which dehisces 

 for two-thirds of its length, with elaters of one 

 spiral, whereas JiingermanniecB have a four-valved 

 capsule, dehiscing to the base, and elaters of two 

 spirals. Other distinctions are also indicated. Dr. 

 Spruce says that " the Jubulece seem to me equiv- 

 alent to nearly all the rest of the sub-order Jiui- 

 gcrmaniiiaccce. The structure of the capsule, and 

 especially of the elaters, is unique amongst Hepati- 

 cai." The leaves oi JubulccB are invariably alter- 

 nate, and it is onl)^ in the female involucres of a 

 hniited number of species (chiefly of Frullaiiia) 



