TIDESTROM—BOTRYCHIUM VIRGINIANUM AND ITS FORMS. 303 
upper portion (16 cm.), with the exception of a few pinnules, is sterile, 
a condition which I have never before observed. (PLATE 102.) 
EXPLANATION OF PLATE 102.—A specimen collected in humid forest along the upper Caldera River, near 
“Camp I,” Holcomb’s trail, above El Boquete, Chiriqui, Panama, altitude 1,450 to 1,650 meters, March 
22 to 24, 1911, by William R. Maxon, no. 5569 (U. 8. Nat. Herb. 675988). Scale slightly less than 4. 
Mr. C. G. Pringle collected a specimen ' of nearly typical B. virgim- 
anum in the State of Hidalgo, Mexico. In this plant the fertile 
segment (including the stalk) is 31 cm. long, while the middle branch 
of the sterile segment is only half as long, a condition normal (at least 
in older plants) in typical virginianum. There is no trace of a 
persisting sterile leaf. 
The South American and Old World material in our collections 
in Washington is too scant and fragmentary to permit much dis- 
cussion. In one specimen? from Ecuador, however, the fertile seg- 
ment is inserted about 1 cm. below the lowermost sterile pinne, and in 
another specimen on the same sheet the position of the fertile segment 
is normal. A further discussion of extra-North American plants 
belongs properly to botanists who are able to avail themselves of 
collections rich in European and Asiatic material and to those who 
have had the opportunity to botanize in South America. 
CONCLUSION. 
The foregoing review of North American material seems to justify 
the recognition of two species, which may be distinguished as follows: 
Plants with persistent leaves and with fertile segments equaling or somewhat exceed- 
ing the sterile segment. 
Botrychium cicutarium (Savigny) Swartz, Syn. Fil. 171. 1806. 
Osmunda cicutaria Savigny in Lam. Encycl. 4: 650. 1797. 
Botrychium virginicum B mexicanum Hook. Bot. Misc. 3: 223. 1833. 
Botrychium brachystachys Kunze, Linnaea 18: 305. 1844. 
Botrychium dichronum Underw. Bull. Torrey Club 30: 45. 1903. 
Plants without persistent leaves and with long-exserted sporophyll (in older plants). 
Botrychium virginianum (L.) Swartz, Journ. Bot. Schrad. 18002: 111. 1801. 
Osmunda virginiana L. Sp. Pl. 1064. 1753. 
Botrychium gracile Pursh, Fl. Amer. Sept. 656. 1814. 
The excellent material collected by Mr. Maxon gives us a good 
insight into the very variable B. virginvanum group and helps us to 
distinguish the two forms proposed by botanists long ago. It would 
save much confusion and add much to the credit of botany if only 
such material could be considered in plant descriptions. 
1U.5S. Nat. Herb. no. 461872. 2U.S. Nat. Herb. no. 50754. 
