BOTANY 



Coleman from Dawley's Wood, Tewin. On No-Man's-Land and the 

 other dry gravelly heaths of Mid Herts such species as Rhacomitrium 

 canescens, which especially affect such localities, will be found. Six of 

 the twelve British species of Pottice occur ; they are, P. recta, truncatula, 

 intermedia^ minutula, Starkeana, and lanceolata, and of these the first and 

 fifth are the rarest. The pleurocarpous mosses are on the whole very 

 well represented. 



THE LIVERWORTS (Hepatica) 



Forty-four species of Hepatica? were known to the Rev. W. H. 

 Coleman as occurring in the county, a list of them being published in 

 Appendix V. to the Flora Hertfordiensis. Among the possessions of the 

 Hertfordshire Natural History Society is a manuscript in Mr. Coleman's 

 handwriting in which the localities are recorded, and these, with a few 

 notes by other observers, were published in the Transactions of the Society 

 in 1893.' Since that time the list has not been added to. 



The following are the genera represented in Hertfordshire, with the 

 number of species in each genus 



MARCHANTIACE.S: 



Marchantia . 



Conocephalus 



Asterella 



Lunaria . 



Riccia 



Ricciella . 



Ricciocarpus 



JUNGERMANNIACE.S: 



Frullania 

 Lejeunea 

 Radula . 

 Porella . . 

 Lepidozia 

 Odontoschisma 

 Cephalozia . 



2 Jungermannia 7 



Nardia . . I 



Fossombronia I 



Pellia . . 2 



Aneura . . 2 



Metzgeria . I 



Sphaerocarpus i 

 ANTHOCEROTACE^: 



Anthoceros . . i 



THE STONEWORTS (Cbaracea) 



The stoneworts, although a very small group of plants, do not fall 

 into any one of the larger classes. Linna?us first placed them amongst 

 the cryptogamic plants (near the lichens), and then amongst the lower 

 phanerogamic plants, in which view he was followed by Jussieu, De 

 Candolle, Brown, and Leman. In 1835 Fries gave them their highest 

 position, considering them to be dicotyledons ; a year or two later End- 

 licher assigned them their lowest position in the middle of the Alga?, 

 which he considered to be the lowest class of plants. Lindley in 1833 

 placed them between the Hepaticae and the Fungi, but in 1845 amongst 

 the Alga?, the view held by Von Martius, Agardh, and Wallroth, all of 

 whom considered them to be Confervae. In 1845 Brongniart placed 

 them (doubtfully) in the Acrogens above the ferns and their allies ; and 

 in 1857 Berkeley referred them to the same class, but put them below 

 the Hepatica?. 2 They are now given a rank equal to that of the ferns, 

 mosses, lichens, etc., the Algae being considered their nearest allies. 



1 Trans. Herts Nat. Hist. Soc., vol. vii. p. 233. 



8 See Lindley's Vegetable Kingdom, pp. xliii.-liv. and 26 (3rd ed. 1853), and Berkeley's Cryptogamie 

 Botany, p. 424 (1857). 



I 65 F 



