136 Dowell: New ferns described as hybrids 



Dav., and D. cristata x spimdosa (Milde) C. Chr. The last has 



been considered by many botanists the same as our Boott's fern, 



but Christensen puts this as doubtful, and in my opinion they are 

 not the same. 



Dryopteris cristata x spinulosa (Milde) C. Chr. 



Aspidhtm cristatwn x spinalosum Milde, Nova Acta Acad. ] 



Carol. 26: 533. 1858. 

 Dryopteris cristata x spimdosa C. Chr. Index Filicum 259. 



Of this fern I have collected specimens near SufTern, N. Y., 

 39 2 7 b , July 23, 1905, and 5273, October 6, 1907, Ocean Terrace, 

 Staten Island, 3pp#a, August 2, 1905, and 50/?, July 15, 1907; 



1905 



24, 1907- 



June 10, 1906, and 5053, J 



This differs from Boott's fern in having glabrous indusia, sori 

 farther from the midvein, in being less deeply cut, having the 

 stipes less chaffy, and the scales a paler brown. 



Dryopteris cristata x intermedia nom. nov. 



Aspidhtm Boottii Tuckerm. Hovey's Mag. 9: 145. 1843. 



Aspidium spinulosum Boottii D.C. Eaton in A. Gray, Man. ed. 5. 

 665. 1867. 



Dryopteris Boottii Underw. Our Native Ferns, ed. 4, 1 17. 1893- 

 This occurs frequently in our woodland swamps. 

 The probability that this fern is a hybrid has been often stated 

 and commented upon, and by many the opinion is held that it is 

 a hybrid between D. cristata and D. spimdosa, as stated above. It 

 differs from that fern in being more deeply cut, usually bipinnate, 

 more chaffy at the base of the stipe, having the scales darker, the 

 indusia and the under side of the blade glandular, and the sori 

 nearer the midvein. 



Dryopteris Clintoniana x intermedia hyb. nov. 



Rhizome stout, chaffy: stipes 10-40 cm. long, densely chaffy 

 at the base with thin light-brown scales, which have usually a 

 darker center ; blades ovate-lanceolate to oblong-lanceolate, 20-75 

 cm. long, 15-25 cm. wide, acuminate at the apex, slightly nar- 

 rowed at the base, pinnate-pinnatifid to twice pinnate; pinnae 

 oblong-lanceolate to triangular-lanceolate, acuminate, broadest at 

 tne base, the upper pinnatifid, the lower pinnate toward the base 



