BOTANY 



GENTIANE* 

 Erytbrtga pukbella, Fries 



BORAGINE& 



Symphytum tuberosum, L. 

 Myosotis illvatica, HofFm. 

 Cynoglossum montanum, Lamk. 



CONVOLVULACE^ 



Cuscuta epilinum, Weihe 



SCROPHULARINEJE 



Verbascum lychnitis, L. 



blattaria, L. 



virgatum, With. 

 Linaria spuria, Miller 



decumbens, Moench 

 Melampyrum cristatum, L. 



OROBANCHE.* 



Orobanche major, L. 



minor, Sutt. 



ceerulea, Vill. 



LAJUATJI 



Mentba ntundifolia, L. 

 Stachys ambigua, Sm. 

 Ajuga chamaepitys, Sckreb. 



CHENOPODIACEJE 



Chenopodium ficifolium, Sm. 



urbicum, L. 



hybridum, L. 



murale, L. 



PoLYGONACE.ffi 



Polygonum minus, Huds. 



dumetorum, L. 



EUPHORBIACEJE 



Euphorbia platyphyllos, L. 

 Mercurialis annua, L. 



SALICINE.S: 

 Salix russelliana, Sm. 



HYDROCHARIDEJE 



Hydrocharis morsus-ranae, L. 

 Stratiotes aloides, L. 



ORCHIDE./E 



Cephalanthera pallens, Rub. 

 Herminium monorchis, Br. 



LILIACEJE 



Ruscus aculeatus, L. 

 Polygonatum multiflorum, All. 

 Allium oleraceum, L. 

 Fritillaria meleagris, L. 

 Gagea lutea, Ker 



JUNCE.S 



Juncus diffusus, Hofpe 

 Luzula Forsteri, DC. 



TYPHACE.S 

 Sparganium minimum, Fries 



NAIADACEJE 



Potamogeton rufescens, Schrad. 



gramineus, Fries 



CYPERACE./E 



Eriophorum latifolium, Hoppe 

 Scbcenus nigricans, L. 

 Carex teretiuscula, Good. 



baenninghausiana, Weihe 



gracilis, Curtis 



xanthocarpa, Degl. (? hybrid) 



strigosa, Huds. 



GKAHIXUK 



Setaria viridis, Beauv. 



Alopecurus fulvus, Sm. 



Phleum phalaroides, Koch 



Agrostis pumila, L. 



Calamagrostis lanceolata, Roth 



Gastridium lendigerum, Gaud. 



Apera spica-venti, Beauv. 



Bromus racemosus, L. 



Hordeum silvaticum, Huds. (Elymus europaeus, L.) 



A few plants enumerated in these lists are probably extinct. The white water-lily 

 (Nympheea alba), first recorded for the county by Izaak Walton in his Compleat Angler (1653), 

 is probably extinct as a wild plant. It has been eradicated from the river Lea, where Walton 

 saw it, by nursery gardeners, and wherever it is now found, which is only in ornamental 

 waters, it has probably been planted. The great burnet (Poterium qfficina/e, Hook, f., better 

 known as Sanguisorba officinalis) has not been recorded since it was first gathered in 1840, near 

 Ashwell in the Cam district. And the star-fruit (Damasonium stellatum\ which was first 

 recorded from its only known locality, Totteridge Green in the Brent district, by Joseph 

 Woods in Turner and Dillwyn's Botanist's Guide (1805), gradually became scarcer, and could 

 not be found there by Coleman in 1858. 



On the other hand several species of recent introduction are becoming thoroughly estab- 

 lished and are gradually extending their range in the county. The most interesting of these 

 are the two smaller balsams (Impatiens fiilva and parviflora). The presence of the former on 

 the banks of the Grand Junction Canal at Harefield was first recorded in 1869, and by 1875 

 it had spread up the valleys of the Colne and Gade, through Rickmansworth and Cassiobury 

 Park, to Hunton Bridge above Watford. The latter was first noticed at Essendon in the Lea 

 district in 1874, and has since appeared in Cassiobury and Ashridge Parks in the Colne dis- 

 trict. The American water-weed (Elodea canadensis of Hooker's flora, much better known as 

 Anacharh ahlnastrum) was introduced into England about the year 1841 ; in 1852 or 1853 '* 

 was first noticed to be nearly choking the river Colne at Watford; and by 1881 it had 



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