8 ENGLISH BOTANY. 



Llanberis, Carnarvon (Professor Babington). In a pool near the top 

 of Ben-Voirlich, Dumbarton (Professor Babington, 1845). Loch of 

 Drum, Aberdeenshire (where I gathered it in 1850). Loch Callater, 

 Braemar (Mr. J. Sadler in 1878). Lake near the Gap of Dunioe, 

 Killarney, and in the upper lake of Killarney, near Glenagh (Dr. 

 Moore). Lough Gowla-na-gower and Lough na-Grooaun, Inish Boffan, 

 Gal way (Mr. A. G. More). 



England, Scotland, Ireland. Perennial. Summer, Autumn. 



Yery similar to I. eu-lacustris, but according to Professor 

 Babington the plants may be distinguished when growing by the 

 " spreading leaves and pale green colour," in contrast " with the dark 

 tint and usually erect leaves of I. eu-lacustris." The only place 

 where I have collected this plant is in the Loch of Drum in 1850 and 

 1851. There the fronds are 2 to 6 inches long, spreading, flaccid, 

 fragile, pellucid, pale green, with a large portion of the base paler : but 

 the North American form, var. Braunii, is described by Dr. Engel- 

 mann as having the " leaves dark, and often olive-green, straight or 

 commonly recurved," while another American variety Boothii has 

 bright green stiffly-erect leaves. Both these American forms have 

 stomata on the leaves, which, so far as I know, have not been 

 observed in any European specimens, except some from ' Iceland ' 

 (Milde). The threads in the interior of the sporangia are more 

 thickened, but the only conspicuous difference between the subspecies 

 is that the tubercles on the macrospores of I. echinospora are very 

 much longer and more acute than in I. eu-lacustris. 



Probably the plant will be found in other stations, having been 

 passed over as I. eu-lacustris. 



Prickly-spored Lake Quillwort. 



SPECIES LL-ISOETES HYSTRIX. Durieu. 



Plate 1828. 



Babenh. Crypt. Vase. Europ. Nos. 101, 102, and 103. 

 I. Duritei, Hook. Brit. Ferns, tab. 26 (non Bc-ry). 



Plant terrestrial. Roots pubescent. Corm 3-lobed, with 3 radiat- 

 ing furrows beneath, its lower part clothed with the persistent and 

 indurated bases of former leaves. Leaves trigonous, filiform, with 

 broad sheathing bases having membranous edges and a tuberculated 

 band on the back, recurved and spreading in a circle, opaque, with 

 numerous stomata. Phyllopodia or indurated bases of the leaves 

 crustaceous, pitchy black, 3-toothed at the apex with ihe central tooth 

 often minute. Phyllodes usually present. Velum complete, wholly 



