Near Swartlär I noticed a mineral spring, but whatever may be its qualities, nobody has yet made any inquiries concerning them.
The river Lulea divides into two branches, not far above the bounds of Lapmark and Westbothnia, one of which is called the little river Lulea, whose origin is among the mountains towards Hyttan, the other
Stor Lulea, running from the alps in Nörbattra.
July 30.
On examining the cultivated Hop (Humulus Lupulus), I found the structure of the female as follows. Calyx consisting of an universal involucrum of four leaves, and a partial one, likewise of four ovate leaves, containing eight florets, each of which has an ovate spatha, of a very large size with respect to the rudiments of the fruit. Petals none. Pistils two, horn-like. Stigmas acute. Seed-vessel none, the base of the spatha enclosing the seed, which is solitary.
The shore of the river Lulea produced, in excessive abundance, the Water Sedum (Tillæa aquatica); likewise the Aquatic Dwarf Plantain (Limosella aquatica). The Spiked Water-grass, with a bent stem, here grew above other plants, twisting its leaves round them, like a sort of bindweed. (Alopecurus geniculatus β. Sp. Pl. 89. See Fl. Lapp. n. 38.)
The Water Sedum (Tillæa aquatica) proved no less plentiful by the sides of the roads.
In the river I gathered an herb, which I was doubtful whether to refer to Stellaria (Callitriche), to Potamogeton, or to the Aponogeton of Pontedera. (This appears to have been the latter, Zannichellia palustris.)
I reached the old town of Lulea in the evening.