1922] 



PFEIFFER MONOGRAPH OF THE ISOETACEAE 121 



dance of living material of the forms concerned. A relatively 

 small representation of dried material is inadequate for the prob- 

 lem. /. longissima is reduced here to a form since there seems 

 no basis for separation but leaf length. /. Perralderiana is re- 

 duced to st variety, differing from the species in having more 

 slender leaves and smaller megaspores. The other species are re- 

 tained in their present rank with the knowledge that they might 

 readily be reduced to varieties, if geographical limitations were 

 not distinct. 



15b. Var. Perralderiana Pfeiffer, comb. nov. 



/. Perralderiana Dur. & LeTourn. in Kralik, PI. Alg. Exsic. 

 157; Milde, Fil. Eur. 282. 1867; Kuhn, Fil. Afr. 196. 1868; 

 Baker, Jour. Bot. 18: 107. 1880, and Fern Allies, 130. 1887; 

 Motel. & Vendr. Actes Soc. Linn. Bord. 36: 354. pi. 11. fig. 7, 8, 

 9. 1883. 



Calamaria Perralderiana Kuntze, Rev. Gen. PI. 2 : 828. 1891- 

 93. 



Like the species in habit except for very fine leaves; mega- 

 spores 380^475 n in diameter, marked with a few large warts 

 and many smaller ones ; microspores 26-33 M long, finely, densely 

 spinulose, sometimes crested. 



Distribution: Algeria. 



Specimens examined: 



Algeria: pool of the fountain of Ai'n Sumta, by the gorges Ak- 

 fadou, eastern Kabylie, 1 August, 1861, Cosson (Gray 

 Herb.), TYPE; "cultivated by Durieu at Jardin de Bot- 

 anique de Bordeaux, coming from Jurajura", 11 July, 1871, 

 LeTourneux (Mo. Bot. Gard. Herb.). 



16. I. tegulensis Genn. Comment. Critt. Ital. (2): 106. 1861; 

 Milde, Fil. Eur. 283. 1867; A. Br. Monatsber. K. Akad. Wiss. 

 Berlin, 608. 1864; Fl. Ital. 1867; Baker, Jour. Bot. 18: 107. 

 1880; Motel. & Vendr. Actes Soc. Linn. Bord. 36: 363. pi. 11. 

 fig. 8-4. 1883. 



7. Tiguliana Genn. Comment. Critt. Ital. (1) : 42. 1861. 



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



Corm 3-lobed ; leaves 5-20, 20-30 cm. long, yellow-green, very 

 fine, erect, with narrow membranaceous margins little elongated 



