It is not without some surprise that we observe here certain plants of our own epoch, which seem to have had the privilege of ornamenting the greater watercourses. Among these we may mention the Water Caltrop, _Trapa natans_, whose fine rosettes of green and dentated leaves float so gracefully in ornamental ponds, supported by their spindle-shaped petioles, its fruit a hard coriaceous nut, with four horny spines, known in France as _water-chestnuts_, which enclose a farinaceous grain not unpleasant to the taste; the pond-weed, _Potamogeton_, whose leaves form thick tufts of green, affording food and shelter to the fishes; _Nympheaceæ_, which spread beside their large round and hollow leaves, so admirably adapted for floating on the water, now the deep-yellow flowers of the _Nenuphar_ now the pure white flowers of the _Nymphæa_. Listen to Lecoq, as he describes the vegetation of the period:--“The Lower Tertiary period,” he says, “constantly reminds us of the tropical landscapes of the present epoch, in localities where water and heat together impress on vegetation a power and majesty unknown in our climates. The Algæ, which have already been observed in the marine waters at the close of the Cretaceous period, represented themselves under still more varied forms, in the earlier Tertiary deposits, when they have been formed in the sea. Hepaticas and Mosses grew in the more humid places; many pretty Ferns, as _Pecopteris_, _Tæniopteris_, and the _Equisetum stellare_ (Pomel) vegetated in cool and humid places. The fresh waters are crowded with _Naiades_, _Chara_, _Potamogeton_, _Caulinites_, with _Zosterites_, and with _Halochloris_. Their leaves, floating or submerged, like those of our aquatic plants, concealed legions of Molluscs whose remains have also reached us. “Great numbers of Conifers lived during this period. M. Brongniart enumerates forty-one different species, which, for the most part, remind us of living forms with which we are familiar--of Pines, Cypresses, Thuyas, Junipers, Firs, Yews, and Ephedra. Palms mingled with these groups of evergreen trees; the _Flabellaria Parisiensis_ of Brongniart, _F. raphifolia_ of Sternberg, _F. maxima_ of Unger; and some _Palmacites_, raised their widely-spreading crowns near the magnificent _Hightea_; Malvaceæ, or _Mallows_, doubtless arborescent, as many among them, natives of very hot climates, are in our days. “Creeping plants, such as the _Cucumites variabilis_ (Brongn.), and the numerous species of _Cupanioïdes_--the one belonging to the Cucurbitaceæ, and the other to the Sapindaceæ--twined their slender stems round the trunks, doubtless ligneous, of various Leguminaceæ.