ENGELMANN THE GENUS ISOETES IN N. AMERICA. 



359 



it his I. MACROSPORA. No date being indicated on the labels, the 

 above-mentioned year is a mere guess. 



1825 (?). Jens Vahl collected in Greenland a small Isoeies., 

 referred to /. lacustris^ which proves to be one of the forms of 

 /. echinospora. 



1S31. J. W. Robbins gathered an Isoeies near Uxbridge, 

 Mass., which I recognize as /. riparla. 



1832. C.J. Moser, who collected for the German Unio itine- 

 raria, obtained specimens on the Lehigh river near Bethlehem, 

 Pa., and near Philadelphia, both of which were distributed to the 

 subscribers as /. lacustris. One of these (in Herb. Bernhardi, 

 now in the Herb. Missouri Bot. Garden) represents /. Engel- 

 manni] another, which I have seen in Europe, is /. riparia. 



1834. Th. Nuttall discovered an Isoeies on the Columbia river 

 in Oregon, which I saw in E. Durand's Herb, with Nuttall's own 

 label, /. opaca ; it was afterwards named I. Nuttallii. 



About the same year Drummond collected " /. lacusiris" on 

 the Saskatchawan, according to Hooker's Fl. Bor. Am. ii. 268, 

 which I have not been able to compare and to identify. 



1840. J. W. Robbins found /. l^cusiris near Uxbridge. 



1842. Rugel discovered an Isoeies in Lake Imonia in Florida, 

 which was soon afterwards distributed in Europe by Shuttleworth 

 under the name of I. flaccida. None of his specimens are be- 

 lieved to exist in America. 



In the same year N. Riehl and myself found near St. Louis, 

 Missouri, the species which from my specimens wasby A.Braun 

 named L Engei.manni. 



1843. Chas. Geyer found in Western Idaho /. Nuiiallii, ac- 

 cording to A. Braun, who examined the specimens in the Kew 

 Herbarium. 



In the same year S. Tuckerman collected /. laciisiris in the 

 Echo lake in New Hampshire. 



1844. Wm. Zantzinger rediscovered the Isoeies on the banks 

 of the Delaware near Philadelphia. His specimens, sent to me, 

 are the type of my I. riparia. 



1845. T. W. Robbins found in Massachusetts /. echinospora^ 

 var. Braunii. 



1848. E. Tuckermann discovered near Boston the species 

 which was by A. Braun named for him I. Tuckermani. 



