139 



figures 6, 7, 8, and 9 show respectively a pinna, a pinnule, an 

 indusium, and a spore of " Aspidmm cristatinnv2^x. Clintonia)iiiin." 

 The pinna unmistakably belongs to a leaf of the sort ordinarily 

 identified as D. Clintoniana, but is not like those of Judge Clin- 

 ton's collection. The leaf illustrated is presumably in the Eaton 

 herbarium to-day, and if it can be determined by the figure, 

 should serve as the type. Rules i° and 2° are inapplicable 

 owing to the exclusion of the Clinton specimen. For purposes 

 of completeness, an amended description of Diyopteris Clintoiiiana 

 is here included. 



^ Dryopteris Clintoniana (D. C. Eaton) Dowell 



Aspidiuni cristatum var. Clintoniamini D. C. Eaton in A. Gray 

 Manual of Botany, Edition 5: 665. 1867. 



Rootstock horizontal, the crown unsymmetrical, with low 

 spreading juvenile sterile leaves, and taller more erect fertile 

 ones, up to 4 feet in length : lamina broadly oblong, acuminate, 

 the pinnae mostly acuminate or long-acute, usually broadest at 

 the base, deeply divided, the divisions oblong, mostly slightly 

 falcate, 8—12, rarely as many as 14 per pinnula (counting 

 those with more than 2 sori, or on sterile or sparsely fertile 

 fronds, those 8 mm. or more long) : sori mostly 6-8 per pinnula, 

 the indusia glabrous, with heavy radial ribs, the cells mostly nar- 

 row, the walls all very sinuate. 



Type in question. 



The problems in connection with Dryopteris Clintoniana are 

 not ended with the fixing of a type. It appears to be in some 

 respects an extremely variable plant, and a study of a wide range 

 of material with a view to determine the limits of this variation 

 is desirable. Its behavior in hybridization also offers an interest- 

 ing field for study and affords moreover evidence as to its dis- 

 tinctiveness in addition to that derived from its own characters, 

 for the hybrids, when compared with the corresponding crosses 

 of D. cristata, maintain for the most part the well-marked differ- 

 ences of the parent forms. But perhaps the best evidence of the 

 distinctiveness is found in the occasional finds of sterile or par- 

 tially sterile intermediates between the two species, the only in- 

 termediates to be found as far as my experience goes. Description 



