[Vol. 9 

 190 ANNALS OF THE MISSOURI BOTANICAL GARDEN 



7. paupercula (Engelm.) Eaton. Proc. U. S. Nat. Mus. 23: 

 649. 1901, and in Gilbert, List N. Am. Pterid. 10: 28. 1901. 



Corm 2-lobed ; leaves commonly 9-30, rarely 60, 5-20 cm. long, 

 dark green, rigid, gradually tapering, with wide membranaceous 

 border at base, extending 2-3 times length of sporangium above 

 level of latter; peripheral strands and stomata lacking;/ ligule 

 short- triangular ; sporangia almost orbicular, 5-6 mm. long, with 

 narrow velum (covering about 1/3 of sporangium) ; megaspores 

 cream-colored, 525-640 (j in diameter, marked with low con- 

 spicuous irregular crests, chiefly simple on the apical faces, 

 branching to form irregular network on basal face; microspores 

 24-42 (j long, spinulose. 



Distribution : Idaho, Wyoming, Colorado, California. 

 Specimens examined: 



Idaho : in water from 6 in. to 6 ft. deep, Lake Coeur d'Alene, 22 

 August, 1897, Henderson 2979 (Mo. Bot. Gard. Herb.) ; in 

 2 ft. of water, Lake Coeur d'Alene, August, 1898, Hender- 

 son (Mo. Bot. Gard. Herb.); in 2 ft. of water, Lake Coeur 

 d'Alene, August-September, 1897, Henderson J+786 (Gray 

 Herb.). 



Wyoming: Yellowstone Park, 1885, Tweedy 416 (U. S. Nat. 

 Herb, and Gray Herb.) ; growing in deep water at north end 

 of Yellowstone Lake, 16 August, 1900, Bessey 1 (N. Y. Bot. 

 Gard. Herb.). 



Colorado: "covering the bottom of Grand Lake in granitic sand, 

 3-4 ft. under the surface of water, abundant, meadow-like, 

 Middle Park," 5 August, 1881, Engelmann (Mo. Bot. Gard. 

 Herb.). 



California: Donner Lake, September, 1887, Curran (Mo. Bot. 

 Gard. Herb, and N. Y. Bot. Gard. Herb.) ; Donner 1 Lake, 

 Shockley (Mo. Bot. Gard. Herb.) ; Castle Lake, mountains 

 about the headwaters of the Sacramento River, alt. 6COO ft., 

 14 August, 1881, Pringle (Mo. Bot. Gard. Herb, and Gray 

 Herb.). 



53. I. Piperi Eaton, Fern Bull. 13: 51. 1905; name only in Fern 

 Bull. 11: 85. 1903; Piper, Contr. U. S. Nat. Herb. 11: 89. 

 1906. 



7. occidentalis var. Piperi (Eaton) Nelson & MacBride, Bot. 

 Gaz. 61: 30. 1916. 



