18 Bulletin Wisconsin Natitral History Society [Vol. 12, Nos. 1 & 2 
vertebrates, the former breeding within tliis association, the latter 
migrating across the bog to the sand banks for this purpose. 
Rana pipiens and Ondatra zihethica both frequent this association, 
and on a few occasions individuals of Querquedida discors were 
seen swimming in the pond. 
The Sedge Association. Scirpus cyperinus^ Carex, Iris versi- 
color, and Typha latifolia are the most abundant plants in the Sedge 
Association, although M enyanthes trifoliata is the most charac- 
teristic. The last named species is confined to this association 
and while common only in local patches in open places, it is, never- 
theless, one of the chief Iwtanical features of this habitat; in other 
bogs of the region, however, it has been observed in the Cassandra 
and Tamarack-Spruce Associations. Steirone^na quadriflorum 
occurs here in numbers and Sphagnum, Sarracenia purpurea, and 
Potentilla palustris invade from the Cassandra Association. 
The roots of the many sedgelike plants form a floating, spongy 
mass which s])rings under foot and often treacherously gives way, 
preci])itating one into the water and mire beneath. The plants 
of this association are mostly rapidly growing forms, and are 
powerful agents in the process of humus deposition and in filling 
in the lake. 
Porzana Carolina, Actitis macularia. Circus hudsonius, Asio 
jlaninieus, and T ehnatodytes p. iliacus, although none of them are 
common in this association, were not found elsewhere in the bog. 
Asm flanimeus, which inhabited a slightly elevated portion of the 
Sedge Association in company with Circus hudsonius, was seen 
only three times — twice in July, 1909, and once in 1912. Rana 
pipiens, Thamnophis sirtalis, Agetaius p. arctolegus, and Microtus 
peimsylvanicus are the most plentiful vertebrates; Rana septen- 
trionalis occurs at the edge of the Aquatic Association; Ondatra 
lar, V)ut their habits and behavior are so widely at variance that it seems improbable that they 
interbreed. For example, Rana septentrionalis is, relatively, a sluggish frog; during the summer 
months it is found along the edge of lakes and streafms, usually with the body partly submerged 
in the water, occasionally on land at the waters edge; it frequently lies partly hidden under a 
log, bark, an overhanging bank, or similar object; when alarmed it utters no sound, makes a feeble 
leap of two or three feet into the water, settles to the bottom and hides in the mud or under some 
object where it is easily captured in the hand. Contrast with the behavior of this frog that of 
Rana clamitans; the latter is an active frog; during the summer months it is almost invariably 
found out of the water on a gently sloping bank; when alarmed it utters a loud, startling croak, 
makes a vigorous leap of five to eight feet into the water, swims some distance under water before 
hiding, where \t remains alert and difficult to capture. There remains, of course, the alterna- 
tive to explain this as “one species having different mores’’ (Shelford, 1912a, p. 92), but one can 
hardly accept this view in the present case. 
