lie gave his opinion that all of the group with simple or irregu¬ 
larly-branched stems formed only one species/' Some of my 
American specimens quite accord with the normal form of our 
plant, and I cannot agree with Koch when he says, “ A nostra 
planta luculenter differt JEquisetum scirpoides , Mich. (. F . reptans , 
var. a, Wahl. FI. Lapp. p. 298), caulibus humilioribus dimidio 
tenuioribus sexangularibus cum vaginis tanturn tridentatis, qua- 
rum dentes persistunt. Caules M scirpoidis revera tricostati 
sunt, sed linea impressa, costarum dorsalis ita excavata est, ut 
strias inter costas sitas eequet.” 
Plate 66. Entire plant and a fertile branch of JEquisetum (§ Hyemalia) varie- 
gatum , Schleich ,—natural size. Eig\ 1. Section of a stem, to show the lacunes, 
— magnified . 
