a _ Tepresents a distinct species of which we have drawn up a MSS. descrip 
670 UnpErRwoop: A REVIEW 
A study of the material represented in the principal Ameri- 
can herbaria together with that in the Berlin, Kew, and Cosson * 
herbaria in Europe has led me to recognize a larger number of 
species from north of the Isthmus of Panama than has been usual. 
A preliminary study is here presented in the hope that it will serve 
to bring out additional light regarding several of the species now 
imperfectly known. 
Synopsis of the North American Species 
Pinnae of sterile leaves 2.5-8 cm. broad. 
Stipes without nodes ; sporophylls with 8-10 pairs of pinnae which are 12-18 cm. 
long and rounded at the base. 1, D. nodosa. 
Stipes with 1-3 nodes.f 
Leaves rounded and abruptly acuminate at the apex ; lowest pinnae scarcely 
half as large as the upper. 2. D. poly we? si 
Leaves tapering to the apex. 3. D. elliptica. © 
Pinnae of sterile leaves under 2.5 cm. wide. 
Leaves with a single terminal pinna; stipes nodose. 
Veins mostly simple, only rarely forking. 
Veins I mm. or more apart. 
Intercostal spaces about 6 to I cm. 4. D. alata. : 
Intercostal spaces 8-10 to I cm. 5. D. Fendlert. 
Veins less than I mm. apart. 
Intercostal spaces 12-13 to I cm. 6. D. stenop ae 
Intercostal spaces 18-19 to I cm. 7. D. cuspidata. 
Veins mostly forked. : 
Margins eroded and curly throughout. 8. D. crispa. 
Margins entire or serrate at the apex. : 
: ae 
Pinnae of sterile leaves acuminate at apex ; sporophylls 0h fe 
5-7 cm. long. 9. D. Jamar 
Pinnae of sterile leaves merely acute. 
i: ; : -4.% cm. long. ‘ 
Sporophylls with pinnae only 3-4.5 ¢ =  -D. Wrightii- 
Sporophylls with pinnae 8-9.5 cm. long. 11. D. Mast sie ve 
Leaves with a pair of terminal pinnae; veins forked’} intercostal spaces #0°" 
to I cm. 3. De 
: pao 
fap De eens ae orld 
* The Cosson herbarium in Paris is one of the finest private herbaria 10 pa . 
and is specially rich in materials from South America, It is particularly intere aay 
students of ferns because it has incorporated with it Fée’s extensive page tne 
types from the West Indies, Mexico, Guiana, and Brazil. We have been ‘a 4 
debted to M. Barratte, the custodian, for his kindness in permitting us to 
rich collection while in Paris in 1900. : char- 
_ TA species from Guadeloupe with nodose stipes resembles D. nodosa he pare 
acter of its foliage, but has sporophylls with only 5-6 pairs of pinnae. tion but this 
a had perhaps best wait more complete information before publication. 
