THE ORIGIN OF NEW VARIETIES OF NEPHROLEPIS BY ORTHO- 
GENETIC SALTATION 
11. REGRESSIVE VARIATION OR REVERSION FROM THE 
PRIMARY AND SECONDARY SPORTS 
OF BOSTONIENSIS"- 
R. C. Benedict 
(Received for publication June 30, 192 1) 
Introduction : A Review of the Characters of the Progressive Sports 
A description of the regressive variations of Nephrolepis exaltata var. 
hostoniensis requires some review of the characters of the progressive sports 
of this form." The nature of these may most simply be indicated by tabulat- 
ing the outstanding facts relating to them. 
1. The progressive varieties so far described all have had their origin by 
vegetative sporting from N. exaltata var. hostoniensis, or its derivatives. 
Reproduction is by bud plants on slender stolons. 
2. Over one hundred new varieties have appeared spontaneously at 
various florists' establishments in the last twenty years. 
3. All these varieties have been discontinuous, i.e., separated from the 
parent form by a definite break in characters — in other words, saltations 
or mutations. These new varieties have not intergraded by slight differ- 
ences into their parent forms. 
4. The evolution of these forms has been orthogenetic, that is, they have 
developed in series in which each character is successively intensified in 
succeeding forms. There are three such orthogenetic series: 
(a) Division series: hostoniensis, once pinnate — Piersoni, twice 
pinnate — Barrowsi, more completely twice pinnate — -Whitmani, three 
times pinnate — Smithi, four times pinnate — Craigi, five times pinnate. 
{h) Ruffling series: hostoniensis, with nearly plane pinnae — Roose- 
velti, pinnae ruffled — sport of Roosevelti, pinnae more ruffled and lobed. 
(c) Dwarfing series: hostoniensis — Scotti — Wagneri, and hostoniensis 
— Giatrasi — sport of Giatrasi; the second and third forms in each case 
are successively smaller than hostoniensis. 
As further evidence of orthogenesis may be cited the fact that combina- 
tions of these three types of variations may occur. Thus, dwarfing may 
1 Brooklyn Botanic Garden Contributions, No. 27, 
- For a full account, see Bull. Torrey Bot. Club 43: 207-234. PI. 10-15. 1916. 
140 
