The Genus Riccardia in Chile. 139 



surface-cells are a little broader, averaging about 25 /x in width 

 along the margin. Between these small surface-cells and the 

 larger cells which make up the interior of the axis the transition 

 is very abrupt. The interior cells are mostly 150-200 fx long and 50 

 /iwide but toward the edge the width may be as much as 100 /x. 

 These large interior cells, which are mostly thin- walled, can be 

 seen clearly through the small-celled surface layer, and constitute 

 one of the most striking features of the species. 



The ordinary branches spread obliquely or widely and are usually 

 3-5 mm. apart on each side of the axis. Although they tend to be 

 opposite their arrangement is far from definite. In rare instances 

 an axial branch is developed. The ordinary branches are quickly 

 limited in their growth and are usually only 3-6 mm. long, 

 although (according to Stephani) they may sometimes reach a 

 length of 10 mm. They ts^per gradually toward the apex, their 

 greatest width being mostly 0.7-0.9 mm., and may be either flat- 

 tened or terete in the outer part. In most cases a primary branch 

 bears one, two or (rarely) three secondary branches on each side, 

 the latter being only 0.3-1.2 mm. long and 0.2-0.3 mm. wide. 

 These secondary branches likewise taper and may be flattened but 

 are much more likely to end in terete and spine-like points. The 

 primary branches (Fig. 3, D, E) show a structure similar to that 

 of the main axis, but the median portion is only eight or nine cells 

 thick and the contrast in size between the superficial and interior 

 cells is less marked, the marginal cells being often 30/* wide and 

 50 IX long. The terete branches, which are often decurved, show 

 an almost circular section (Fig. 3, F), about six cells across in 

 every direction, and the cell dififerentiation is very slight. Even 

 here, however, the small-celled band, which forms so marked a 

 feature of the main axis and primary branches, can still be distin- 

 guished as a strip only a few cells wide. 



Massalongo's description of R. Spegazsiniana was drawn wholly 

 from sterile material, and the writer has been unable to demonstrate 

 either male or female inflorescences in the specimens at his disposal. 

 According to Stephani the female inflorescence is borne on a very 

 short and thick decurved pinnule, strongly papillose in the outer 

 part ; but he gives no information regarding the male inflorescence 

 or the structures derived from the fertilized archegonia. 



Stephani's description and figure of Aneura spiniloba are 



