STATISTICS OF METASPERMAE. 743 
The progression of percentages from Monocotyledones to 
Metachlamydeze, as read in the last columns of the three pre- 
ceding tabulations, gives interesting testimony to the correct- 
ness of the views (by no means new) that are presented in the 
paragraphs above. 
certainly instructive. 
As compacted below this progression is 
Arb. Shrubby - Herb. 
per cent. per cent. per cent. 
Monocotyledones ...............6+ .0 0.6 99.4 
Archichlamydeae .............-.. 10.0 16.3 74.0 
Metachlamydeae............. ... 1.8 tel 91.0 
The differences are widest between the monocotyledonous 
and least between the archichlamydeous percentages. 
The three habitat-elements may now be. considered. 
In 
Table J is listed the aquatic element. 
J. Table of Aquatic Metaspermae Indigenous to the Minne- 
sota Valley. 
Monocotyledones. 
. Potamogeton natans. 
. Potamogeton fluitans. 
. Najas flexilis. 
. Elodea canadensis. 
nsew. Potamogeton amplifolius. se. Vallisneria spiralis. 
nse. Potamogeton perfoliatus. se. Zizania aquatica. 
new. Potamogeton heterophyllos. new. Panicularia fluitans. 
nse. Potamogeton gramineus var. new. Scirpus fluviatilis. 
zizii. nsew. Scirpus lacustris. 
se. Potamogeton illinoensis. nsew. Heleocharis palustris. 
nsew. Potamogeton pusillus. nsew. Lemna minor. 
new, Potamogeton rutilus. nse. Lemna perpusilla. 
nsew. Potamogeton pectinatus. nsew. Lemna trisulca 
nsew. Potamogeton lucens. nsew. Lemna polyrbiza. 
new. Potamogeton praelongus. se. Grantia brasiliensis. 
nsew. Potamugeton lanceolatus. se. Grantia columbiana. 
new. Potamogeton zosteraefolius. nse. Pontederia cordata. 
new. Potamogeton foliosus. sew. Heteranthera dubia. 
nsew. Zanichellia palustris. 
Archichlamydeae. 
se. Polygonum hydropiperoides. 
. Polygonum amphibium. 
se. Nelumbo nelumbo. 
. Brasenia peltata. 
. Leuconymphaea reniformis. 
.se, Leuconymphaea ordorata. 
. Nymphaea advena. 
. Ceratophyllum demersum. 
. Ranunculus lacustris. 
. Ranunculus aquatilis var. 
trichophyllos. 
Ranunculus aquatilis var. 
caespitosus. 
Ranunculus circinnatus. 
nsew. Stellaria verna. 
nsew. Hippuris vulgaris. 
se. Myriophyllum heterophyllum 
se. Myriophyllum verticillatum. 
. Myriophyllum spicatum. 
new. 
new. 
Metachlamydeae. 
se. Nymphodes lacunosum. 
. Mimulus glabratus var. 
. jamesii. 
new. Veronica anagallis. 
se. Utricularia cornuta. 
new. Utricularia intcr media. 
new. Utricularia minor. 
nsew. Utricularia vulgaris. 
nse. Bidens beckii. 
