[Vol. 9 

 134 ANNALS OF THE MISSOURI BOTANICAL GARDEN 



placed at present with /. Nuttallii, rather than with I. Orcuttii, 

 with which Eaton placed it. 



These two species are very close to each other, and with fur- 

 ther evidence /. Orcuttii may prove a variety of /. Nuttallii. 



28. I. humilior A. Br. Linnaea 25 : 722. 1852. 



/. HookeriA. Br. Monatsber. K. Akad. Wiss. Berlin, 538. 1868; 

 Motel. & Vendr. Actes Soc. Linn. Bord. 36 : 340. 1883. 

 Calamaria humiiior Kuntze, Rev. Gen. PL 2: 828. 1891-93. 



I. Stuartii A. Br. Monatsber. K. Akad. Wiss. Berlin, 539. 1868 ; 

 Motel. & Vendr. Actes Soc. Linn. Bord. 36 : 339. 1883. 



Corm compressed, 2-lobed; leaves somewhat coarse, rigid, 

 tough, attenuate toward apex, obtuse, with somewhat thick, dark 

 epidermis; stomata lacking; ligule short, cordate 1 triangular; 

 velum complete; sporangium small; megaspores 650-770 \\ in 

 diameter, with many small, little elevated, sometimes confluent 

 tubercles on all faces ; microspores 30-32 p long, very short den- 

 ticulate-muricate. 



Distribution : So. River Esk, Tasmania. 



The characters on which Braun separated the species /. Hookeri 

 from /. Stuartii (the two were originally included in the species 

 /. humilior by him) hardly seem of more than ecological signifi- 

 cance (as softness of leaves) or are within the range of variation 

 in any species (as dark coloring at the base of the leaves). Fur- 

 ther he used only one specimen on which to base /. Stuartii. It 

 would seem to the writer who has only the description on which 

 to base judgment that the relation between these two is closer 

 than as adjacent species, and they are accordingly united in the 

 original /. humilior A. Br. 



29. I. melanospora Engelm. Trans. St. Louis Acad. Sci. 3: 

 395. 1877, and 4: 383. 1882; Baker, Jour. Bot. 18: 69. 1880; 

 Motel. & Vendr. Actes Soc. Linn. Bord. 36: 359. 1883; Chap- 

 man, Fl. Southern U. S., ed. 2, 672. 1889; Small, Fl. Southeast- 

 ern U. S. 25. 1903. 



Calamaria melanospora Kuntze, Rev. Gen. PL 2 : 828. 1891-93. 



Corm 2-lobed; leaves 5-11, 2.5-7 cm. long, slender, tapering 

 very gradually to apex, almost setaceous, light green, spreading; 

 stomata present; peripheral strands none; ligule small, triangu- 

 lar; sporangium orbicular, 1-2 mm. long, completely covered by 



