08 A SYNOPSIS OF THE SPECIES OF ISOETES. 



with small, regular, rarely confluent papillae. Microspores 

 minutely papillose or nearly smooth. 



Hab. California, on the eastern declivity of the Sierra Nevada, 

 alt. 7000 feet, Bolander ; discovered in 1866. 



8. I. Stuaktii, A. Br. in BerL Monatber., 1868, 539. — I. ImmiUor, 

 F. M. ; A. Br. in Linn^ea, 1852, 722, ex parte. — Bootstock 2-lobed. 

 Habit of/, lacustris. Leaves 4-6 in. long, pale green, diaphanous, 

 narrowed gradually to the point, without stomata or accessory 

 bast-bundles. Sporange small, globose; veil complete. Macro- 

 spores with very numerous tubercles, which are sometimes 

 confluent. 



Hab. Tasmania, in the South Esk Biver, C. Stuart ! 1. 

 Hookeri, A. Br. loc. cit. 9 from the same station, seems to be 

 another form of the same species, with stiff er dark green leaves 

 narrowed suddenly at the tip, and macrospores with smaller 

 distinct tubercles. 



9. I. Lechleri, Metten. Fil. Lechler, ii. 36 ; A. Br. in Verb. 

 Branden, 1862, 35. — Bootstock 2-lobed. Leaves 12-20, stouter 

 than in lacustris, 3-4 in. long, T l T in. diam. at the middle, dark 

 green, flexible, diaphanous, tapering gradually to an acute point, 

 without stomata or accessory bast-bundles, the broad membranous 

 margin decurrent from the dilated base running half-way up the 

 lamina. Sporange globose ; veil complete. Macrospores middle- 

 sized, smooth. Microspores minutely tubercled. 



Hab. Cordilleras of Peru, Lechler, 1937 ! I. socia, A. Br. I c. 

 36, was afterwards regarded by him as a form of this species. /. 

 Karstenii, A. Br. loc. tit., gathered by Dr. Karsten at a height of 

 8000 feet in the Andes of New Granada, differs only by its 

 muricated" microspores. 



Group 2. Subaquatice.— Species inhabiting shallow water. 



So 

 I. 



Leaves with a few stomata, but without either accessory 

 bast-bundles or persistent bases. 



10. I. Bolanderi, Engelm. in Amer. Nat., 1874, 676.— I. cali- 

 uca, Engelm. MSS. olim.— Bootstock deeply 2-lobed. Habit of 

 echinospora. Leaves 5-20, 2-41 in. long, i-i lin. diam., 

 tapering to a fine point, diaphanous, bright green, with stomata, 

 but without accessory bast-bundles. Sporange mostly oblong, 

 unspotted, covered £-i by the veil. Macrospores small, finely 

 granulated. Microspores more or less papillose or spinulose. 



Hab. Sierra Nevada of California, in ponds and shallow lakes 

 at 5000-10,000 ft,, Bolander. Var. Parryi, Engelm., from the 

 falls of the \ellowstone, differs by its rather smaller macrospores 

 and almost smooth microspores. 



ana 11 '*' S^^ 1 ' A ' B *'> En gelm. in Gray Man., edit, v., 

 0,6.— Lootstock 2-lobed. Habit of /. eehmotpora. Leaves 10-30, 

 o-4 in. long 4 lin. diam. at the middle, bright green, diaphanous, 

 tapering to the point, witb a few stomata, but without accessory 

 hist-lmndles. Sporange small, globose, sometimes spotted; veil 

 partial. Macrospores middle-sized, the upper half covered with 



