THE FERN BULLETIN 



13 



this extreme form, which stands in much the same re- 

 lation to N. cristatum that Asplenium ebenium serra- 

 tion does to the type. Mr. Poyser sends the following- 

 description : 



Nephrodium Cristatum Clintonianum f. Sil- 

 vaticum f. nov. 

 Rootstock as in the type : fronds averaging as large 

 as the sub-species ; pinnae long-stalked, broader than 

 in the normal form, as wide at base as in the middle : 



Pinna of Nephrodium Cristatum Clintonianum silvaticum Poyser. 



pinnules distant, linear-oblong, sharp-pointed, deeply 

 serrate or toothed, the teeth often serrulate. 



Found in Delaware County, Pennsylvania. Type 

 No. 534 in the herbarium of W. A. Poyser. 



In the original description Prof. Eaton says that the 

 fertile and sterile fronds of Clintonianum differ in 

 habit, but in the present form they apparently do not. 

 The fern was found in a deep and shaded ravine and 

 has maintained its form unchanged for at least three 

 years. Recently there has been shown a disposition to 

 consider Clintonianum a species distinct from N. cris- 

 tatum. In that case the species would be Nephrodium 

 Clintonianum and the form N. Clintonianum sylvati- 

 cum. Those who prefer Dryopteris will of course call 

 the form Dryopteris Cliutoniana sylvatica. 



