GENUS i. 



QUILLWORT FAMILY. 



2. Isoetes Tuckermani A. Br. Tuckerman's 

 Quillvvort. Fig. 119. 



Isoetes Tuckermani A. Br. in A. Gray, Man. Ed. 5, 



676. 1867. 

 Isoetes Tuckermani borcalis A. A. Eaton, Fernwort 



Papers 10. 1900. 

 Isoetes Han-eyi A. A. Eaton, Fernwort Papers it. 1900. 



Submerged or rarely partly or wholly emersed 

 during very dry seasons ; leaves 10-40, very slender, 

 tapering, olive-green, quadrangular, 2'-$' long, with- 

 out peripheral bast-bundles, the outer recurved; 

 sporange oblong, mostly white, its upper one-third 

 covered by the velum; macroscpores 440-785 M in 

 diameter, with wavy somewhat parallel and branch- 

 ing ridges on the upper half, separated by the three 

 converging ridges, the lower covered with an ir- 

 regular network ; microspores 26-42 M long, nearly 

 smooth, or with minute spines. 



In ponds, Newfoundland to Massachusetts and Con- 

 necticut ; clustered in shallow water. 



3. Isoetes hieroglyphica A. A. Eaton. 

 Warty Quillvvort. Fig. 120. 



Isoetes hieroglyphica A. A. Eaton, Fernwort 

 Papers 10. 1900. 



Submerged with a bilobed trunk. Leaves 

 10-20, 2$'-3' long, blunt at the apex, without 

 stomata; sporange spotted with dark cells, 

 covered one-third to two-thirds by the velum ; 

 macrospores 486-720 n in diameter, polished, 

 covered with bold vermiform, subconfluent 

 and somewhat reticulated ridges, becoming 

 naked near the equator; microspores 31-44 P- 

 in diameter, distinctly verrucose. 



Nova Scotia to Quebec and Maine ; usually 

 growing in ponds and lakes. 



4. Isoetes Braunii Durieu. Braun's Quillwort. 

 Fig.' 121. 



Isoetes Braunii Durieu, Bull. Soc. Bot. France, n : 101. 



1864. 

 Isoetes echinospora van Braunii Engelm. in A. Gray, 



Man. Ed. 5, 676. 1867. 

 Isoetes echinospora Boottii Engelm. in A. Gray, Man. Ed. 



5, 676. 1867. 

 Isoetes echinospora robusta Engelm. Trans. St. Louis 



Acad. 4: 380. 1882. 

 Isoetes echinospora muricata Engelm. in A. Gray, Man. 



Ed. 5, 676. 1867. 



Submerged or in dry seasons emersed, leaves 10-70, 

 tapering, soft, green. 3'-i2' long, without peripheral bast- 

 bundles, bearing stomata only toward the tip ; sporange 

 orbicular or broadly elliptic, spotted, one-half to three- 

 fourths covered with the velum ; macrospores 400-620 M 

 in diameter, covered with broad spinules _ which are 

 often slightly confluent and incised at the tips; micro- 

 spores 25-32 M long, smooth. 



Labrador and Greenland to Alaska, south to New 

 Jersey, Pennsylvania and California. 



