Page:VCH Hertfordshire 1.djvu/91

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BOTANY Verbascum lychnitis, Orobancbe ccerulea, Cephalanthera ensifolia, Gagea /utea, Carex bosnninghausiana (hybrid), C. xanthocampa (? hybrid) and Phleum pracox. Eight Rubi are not included in this enumeration, not being considered distinct species by Sir Joseph Hooker. They are Rubus affinis, R. tbyrsoideus, R. fusco-ater, R. Sprengelii, R. glandulosus^ R. birtus, R. Bellardi, and R. pseudo-idceus. Of the 893 species of indigenous Hertfordshire flowering plants there are about 1 1 o not recorded as native plants in Cambridgeshire, about 1 20 are wanting in Bedfordshire, 170 in Buckinghamshire, 140 in Middlesex, and 100 in Essex. On the other hand, Cambridgeshire has 55 indigenous species which are wanting in Herts, Beds has 30, Bucks 22, Middlesex 34, and Essex 56 (exclusive of its coast plants). Doubtful records are in all cases excluded. These figures might be very much modified if the botany of each of the counties were equally worked up. Taking the number of species in any adjoining county which are absent from Hertfordshire as the best index of the degree of relationship, it would appear that the flora of Bucks is the most nearly allied to that of Herts, and that those of Cambridge and Essex are the most divergent from that of Herts. This is just what might be expected from the physical features and geological structure of these counties. The floras of Cambridge and Essex have also a more northern or north-eastern facies than that of Hertfordshire, which, as previously stated, is of a decidedly southern type. The large number of Hertfordshire species which have not been recorded from Buckinghamshire is probably due to the flora of that county not having been so thoroughly investigated as ours has been. The following table gives a list of the Natural Orders of Phanero- gamia which are represented in the county, with the number of genera and species in each Order, and also the number of species which have been reported but are excluded either because they cannot be considered to be indigenous or because the evidence of their occurrence is open to doubt. The general classification is that of Sir J. D. Hooker, but the numbers indicate the genera and species enumerated in Pryor's Flora of Hertfordshire, The number of species given in the table does not exactly tally with the number on page 557 of that work. The total number of flowering plants and ferns is there stated to be 1,1 16, of which 26 are ferns, leaving 1,090 flowering plants, of which 898 are considered to be indigenous. Two species have since been added the oxlip (Primula elatior), a native plant, and the alkanet (Ancbusa officinalis)^ an alien. 1 The soapwort (Saponaria officinalis) being a denizen, and the water-thyme (Anacbaris alsinastrum) being an introduced species, have been relegated to the excluded species, and so also have Wallenbergia bederacea, Pyrola media, Euphorbia stricta, and Carex canescens as having been included in our flora on insufficient evidence. The 898 numbered species in Pryor's Flora are thus reduced to 893, and the 192 excluded species are increased to 199, giving a total of 1,092. 1 See Tram. Herts Nat. Hist. Soc. vol. x. p. ix. (1901). I 49 E