ENGEI.MANN THE GENUS ISOETES IN N. AMERICA. 361 



1875. G. D. Butler discovered in the Indian Territory the spe- 

 ■cies named for him I. Buteeri, and with it a new locality for 

 J. melanopoda, 



187S. C. G. Pringle found in Lake Champlain the form of /. 

 echinospora^ which I have designated as var. robusta. 



1879. ^' E.Jones met with L Bolanderi in Utah. 



18S0. A. Gattinger discovered near Nashville, Tennessee, a 

 /, Butleri^ var. immaculata. 



1881. I collected Z lacustris var. paupercula in Grand 

 Lake, Middle Park, Colorado, and C. G. Pringle found the same 

 in Northern California. 



2. PUBLICATION. 



1753, Linnaius published in his Species Plantarumy ed. i., his Isoetes 

 Jacustris, the only species known to him. 



Neither Michaux nor any of the older writers on American 

 plants knew of any North American Isoetes. 



1816. Pursh, Fl. Am. Sept. ii. 671, mentions '' /. lactistris^^ 

 from Oswego river. Western New York, which is most probably 

 /. echinospora^ var. Braunii^ the only species thus far known 

 from that region. 



1818. Nuttall, Gen. ii. 253, has '^7". lacustri£^ from the miry 

 shores of the Delaware near Philadelphia, which cannot be any 

 other than I, riparia ; he also gives Pursh's habitat. 



In the same year Barton, Fl. Philad, ii. 213, has '^7. lacustris'* 

 from Philadelphia, which may include both /, riparia and /. 



Engelm anni. 



1824. Elliott knows no Isoetes. 



1826. Torrey (Comp. FL North. & Middle States) gives as 

 habitat 0^615, 7. lacustris^'' bottoms of lakes, evidently without 

 having himself seen it. 



In the Flora Cesti'ica of the same year Darlington does not 



mention the genus. 



1827. Sprengel, Syst. Plant, iv. 9, knows only /. lacustris with three 

 varieties. • 



1S33. Beck in his Botany repeats Pursh's and Nuttairs lo- 



•calities. 



1840. Hooker, Fl. Bor. Am, ii. 268, mentions " 7. lacustris'* 



from the Saskatchawan. This may be the true lacustris or a 



