50 LEAFLETS, 
imens, namely, from the shores of the Mississippi at Winona, 
Minnesota, I have the aquatic state in flower, communicated by 
Professor Holzinger of the State Normal School at that place, 
who collected it in 1897. The leaves, evidently floating, at 
least the lowest, are not quite as large as in my specimens, but 
are as perfectly glabrous, only the margins being either merely 
scabrous-serrulate, or with the hair-points developed into what 
approaches the spinulose-serrulate. The spikes are linear and 
about 2 inches long, of a rich rose red; the bracts uncommonly 
long-pointed, cuspidately however rather than acuminately, the 
very apex being blunt. The peduncles are slender, and very 
delicately glandular-hirtellous. The specimens give no hint of 
any close affinity for that other long-spiked aquatic of north- 
ern Iowa, P. plantaginea. 
The Neckerian Cactaceous Genera. 
In this exclusively American family of plants at least five of 
the genera now everywhere recognized as such are pre-Linnæan. 
Melocactus, Cereus, Opuntia, Phyllanthus, and Peireskia had all 
been published anteriorly to the year 1753, in which year Lin- 
næus reduces them all to one genus, assigning it a new name, 
Cactus. Moreover, among the twenty-two so-called species enu- 
merated in the Species Plantarum of that date are the types of 
four other genera now everywhere accepted as such, namely, 
Mamillaria, Pilocereus, Nopalia and Phyllocactus. 
Thus the types of nine distinct genera, as men now perceive, 
were embraced within the Cactus of Linnaeus. 
There were two botanists of the time who entered each his 
own protest against this jumbling together of incongruities, 
Adanson and Miller. The former of these did not so greatly 
improve the situation, distributing as he did all the Linnean 
species between the two pre-Linnæan genera, Opuntia and Cer- 
cus; though on an excellent type which Linnzus had ignored, 
he proposed a new genus Harviota, the equivalent, I think, of the 
more recent Rhipsaiis. It is also to be noted that he rejected as 
being the mere synonym that it truly is, the Linnæan Cactus. 
