2 



THE FERN BULLETIN 



conditions, as to leave little doubt that they were two 

 distinct species. The third and last time it was found 

 on the west side of the river, the other two stations 

 being on the east side. The plants were on shelves of 

 rock bordering- the entrance to what is called "the old 

 river channel/' or a former bed of the Wisconsin now 

 abandoned, but forming a lagoon. Fortunately luci- 

 diilum and porophilum were here so close together as 

 to make a mixed association, so that a fine chance was 

 offered to see if there were intergradings. But none 

 were detected, each preserved its distinctive characters. 

 Some examples of porophilum being the most marked 

 of any I had seen. As the patch was not a large one, 

 every plant could be individually examined, but they 

 were as unlike as in cases where they were found grow- 

 ing apart. I had in the meantime come across L. lu- 

 cid ulum in another ravine or narrow rock cutting, the 

 Witches Gulch, which, though smaller than usual, was 

 otherwise well marked and easily identified. Both 

 kinds, as far as my observations went, are infrequent 

 in the Dells, the L. porophilum seemingly better repre- 

 sented. 



The characters most apparent to the unaided eye 

 are the clustered stems and their small size, in this 

 reminding one of L. Sclago. A closer inspection shows 

 that the stems are completely vertical, or the horizontal 

 part when present but three or four inches long, giv- 

 ing a slight horizontal turn, or perhaps a mere bend 

 from a vertical direction. This is quite different from 

 most examples of L. lucidtdum. The narrower and es- 

 sentially entire leaves are a good character. On com- 

 paring the sporangia those of porophilum are found 

 to be 1.2 — 1.5 mm. long, averaging about 1.35 mm., 

 those of luciduhnn 1.5 — 1.75 mm. mostly about 1.7 

 mm. The latter have a broader and somewhat deeper 



