286 



The use of the binomial D. dilatata is in agreement with a 

 common practice in Europe, and has been supported, and rightly 

 as it seems to me, by many well-known fern students. D. inter- 

 media (Muhl.) Gray, which does not occur in Europe, I believe to 

 be similarly distinct, and hope later to give sufficient reason for 

 this opinion. 



Osumnda cinnainoniea L. 



Two aberrant forms of this species were noted during the sum- 

 mer. The first was a physiological freak, apparently a variant 

 from the frondosa form which is known to occur on burnt-over 

 land, as was the case at the locality in question, a rctfidside swamp 

 in the town of Cornwall, Ct. The peculiarity of the frondosa 

 form is the replacement of some of the fertile pinnae by green 

 vegetative ones so that a single frond shows both sorts. In the 

 present instance, the fro7idosa form was not seen but apparently 

 the same result, an increase of the vegetative tissue, was attained. 

 The fronds appeared strongly crested owing to a more or less 

 irregular enlargement of the pinnulae which, besides being ex- 

 panded and curled, were mostly deeply dentate. Few fertile 

 fronds were seen. 



The other form was first found by Miss Harriet Mulford near 

 Hempstead, Long Island, where several plants were seen. Later 

 I found two plants in the Cornwall swamp above mentioned. 

 The peculiarity in this consisted in an excessive development of 

 the lower basal pinnulae which in many cases were at least half as 

 long as the pinnae themselves. As the fronds were nearly erect, 

 and the pinnae about horizontal, the effect was to give the fronds 

 a thick plumy appearance, making the plants exceptionally attrac- 

 tive from a horticultural standpoint. 

 Columbia University. 



