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 BOTANY known species, though not large, is for a lowland and mostly alluvial district a moderately good one. About 220 species have been recorded, a number which compares favourably with most of the adjoining counties, though as we proceed westwards, and the fertile alluvial valleys of the eastern and midland counties give place to the more rocky streams and harder exposed strata of the west, we find, as might be expected, a richer flora of the lower orders of plants. The development of Cryptogamia in a district is probably as a rule in an inverse ratio to its agricultural pro- ductiveness. We cannot therefore expect a very rich moss-flora in a county so highly cultivated as Northamptonshire, where there is an entire absence of peat bogs, a total lack of any natural outcrop of hard rock, where the rivers all run (if the term may be allowed to our sluggish streams) through alluvial valleys, and where heaths and other waste lands are for the most part conspicuous by their absence. Even the large tracts of wood and forest land for which the county is remarkable, while exuberant in fungi, do not add largely, in proportion to the area they cover, to the richness of our moss-flora ; for being to a great extent on clay soil, at low elevations, and with scarcely any water beyond a few small ponds, they present but little variety of surface, and their contribu- tion towards our moss-flora with certain exceptions lies rather in the multiplication of individuals than in the number or rarity of their species. The chief interest of our moss-flora is therefore not to be looked for in a great variety of species, or a great profusion or high development of individuals, but rather in its somewhat special character as determined by the nature of the soil and of the various other substrata on which these plants are found. Perhaps the most noticeable features are the almost entire absence of any quantity of Sphagna or peat-mosses, the presence of a characteristic flora on the oolitic limestone, and the traces of an earlier, richer moss-flora, now in process of extinction through various causes, of which the development of agriculture is undoubtedly the chief Few counties can be so poor in Sphagna as Northamptonshire. A real peat bog does not occur throughout the county, and each of the four species of Sphagnum that occur is confined to a single station, and even there is found over a space of a few square yards at the most. Moreover of these four species two, S. acutifolium and S. intermedium, are only found in pools in a now disused clay-pit, and can have no claim to be considered as truly native in our county ; while the two remaining species exist but as remnants of an older flora, and their ultimate dis- appearance is doubtless but a question of time. The oolitic limestone beds that appear over a great part of the surface of Northamptonshire produce a somewhat distinct moss-flora of their own. Characteristic mosses are found on the stone walls in the northern districts, on the mud cappings of our walls throughout the county, and in the calcareous bogs of the extreme north and south. No species are known to occur that are not found in other counties, but I 81 G