io6 PROCEEDINGS COTTESWOLD CLUB 1913 



to be Roman, and authenticated by an uninscribed altar presented by the 

 author to the Archaeological Institute, exists on the Hill to the North of 

 Stroat and Madgetts. Coins have been lately found in Tidenham Church- 

 yard, and a Roman position discovered on the cliffs in Sedbury, within this 

 parish, as described in subsequent pages." [J-S.] 



The botanical work of the excursion was carried out almost entirely on 

 Tidenham Chase. This is an extensive heath area at a considerable elevation, 

 due to the occurrence of a Millstone-Grit-like deposit which in places caps the 

 limestone district through which the Wye here flows. The character of the 

 flora changes at once with the change of soil. The calcophile species — Rock- 

 rose, Yew, Whitebeam, and the like — practically cease : the rare things of 

 the Wye Cliffs, such as Sedum rupestre, Viola calcarea, are not to be found. 

 The Heather and the two Heaths, Erica cinerea and E. tetralix. along with 

 the Gorse, the Foxglove, and the Whortleberry, compose the mass of the 

 vegetation, give a distinct facies to the whole district, and account for the 

 peaty nature of the soil. The coarser sandy nature of the sub-soil, the pre- 

 sence of peat, and the much greater frequency of water, combine, with an 

 enforced absence of cultivation, to account for almost every noteworthy 

 botanical feature of the neighbourhood. The absence of these factors in a 

 district like that of the Cottes wolds, and their presence, or the presence of 

 similar factors in the colliery districts of the Forest of Dean, serve to show the 

 connection of geological cause and botanical effect. 



A few interesting cases of identity only serve to point the general contrast. 

 The best one to mention is that of the fragrant Orchid, Habenaria conopsea, 

 which is found in identical form both on the dry or wet spots of Tidenham 

 Chase, and on the very driest slopes of the Cotteswolds, such as Sclsley Hill 

 or Rodborough Common. We may contrast with this the common Spotted 

 Orchis. On the limestone, whether on the Carboniferous Limestone of 

 Tutshill or that of the Oolitic Series of the Cotteswolds, it is found in a form 

 which (under the name of Orchis maculata) shows three equal lobes to the 

 lower lip of the corolla : but on the heathland, besides other variations, it 

 differs by a great broadening of the two side lobes and a shortening and 

 shrinking of the central lobe, which gives to the flower a new facies, and a new 

 name. Orchis ericetorum. 



The drier parts of the heath have their own peculiar vegetation, including 

 the above-mentioned plants, several grasses (especially the rigid wiry Nardus, 

 and the beautiful Aira flexuosa, the " Hair-grass "), little eyebrights, and so 

 on. The great prize, however, is the local Viola lactea, a violet with pale blue 

 or white flowers and very narrow leaves. Tidenham Chase, indeed, is prob- 

 ably the only place in England where this violet is known to hybridise with 

 the common broad-flowered Dog Violet, V. Riviniana. V. lactea is here in 

 considerable abundance, and so is the true Dog Violet, V. canina, which also 

 occurs in a wood belonging to the President of the Club at 200 feet less eleva- 

 tion. It is quite possible that some of the puzzling forms found were hybrids 

 between V. canina and F. lactea, but the specimens must be submitted to 

 experts before a decision can be come to. 



Perhaps the group of plants found in the wetter spots of the Chase 

 excited the most general interest. A pond or two and a number of shallow 

 gullies, widening here and there into bits of bog, sometimes containing quanti- 

 ties of Sphagnum — that is the sum total of the wet ground. Two lots of 

 Narthecium were most welcome, a scarce plant in Gloucestershire and rarely 

 flowering there, though near Bridport last year we saw a bog of many acres 

 simply yellow with its fragrant spikes. A tiny white Buttercup with ivy- 

 shaped leaves, Rantf.uiilus hederaceiis, occurred in a few spots ; a square yard of 

 Adder's-tongue fern ; a pond full of a beautiful representative — Nitella opaca 

 of a low type of botanical organisms called CharacecB. The Nitella has long 



