282 CORRESPONDENCE. 



I made an excursion tliitlier on August 17th, with the object of looking up 

 and recording, if worth while, any rare or interesting plants. A single 

 visit, and that so late in the year, can hardly give a fair idea of the flora 

 of a district ; however, I submit to your readers some notes on that 

 excursion. Starting from Birdinghury Station, on the Kugby and 

 Leamington line, I noticed, just outside the station, Lotus tenuis, Sison 

 Amomum, Siluus pratensis, Carduus eriophorus, Senecio erucifolius. In 

 former years I have turned up Galium tricorne, Linaria spuria and 

 Elatine in the first coi-n-field, adjoining the road to Frankton. Leaving 

 Birdinghury village, on my way to the wharf, I observed Scahiosa colum- 

 biiria and Carduuti acauli", both growing abundantly in a meadow on the 

 right of the road, some 300 or 400 yards x^ast a windmill, and a httle further 

 on Brachijpodium pinnatum growing with B. siilvatieum, Silote injlata, and 

 Picris hiemcioidcs in abundance. From Birdinghury Wharf I followed 

 the canal to Napton, observing on my way Spar(jaiiium simplex, Alisma 

 lanceolata, Lotus tenuis again in plenty, and close to Napton Rume.v luridis. 

 By the reservoir I saw Ncisturtium ampltihiuni, Helmintliin echioides, 

 Poli/gonum ampliihium and terrestre, Stadnjs jiahistris, Potamocjeton lucens, 

 Juncus htmprocarpus and compressus, Carex Itirta; in a cornfield 

 on Napton Hill were Centtnirea Scahiosa, and a plant which 

 seemed to be some hybrid form, possibly Stachijs amhigua, a hybrid 

 between S. 2)(iJiistris and si/lvatica, but much more nearly approaching 

 the former than the latter. In fact, it appeared to differ from S.jMhistris 

 only in ha%-ing less elongated racemes, terminating somewhat abruptly, 

 all the leaves shortly petioled and oblong-lanceolate, and in its habitat, 

 growing as it did in a dry cornfield on a hill of considerable elevation, 

 (from which, by the way, I obtained a magnificent view of the surrounding 

 country,) and not a single specimen only, but in gi-eat abundance. The 

 leaves are all shortly petioled, petioles one to three lines long, smaller 

 than in S. palusfris, rather crenate than serrate, and the whole plant is 

 smaller generally than in S. palustris. It has been suggested to me that 

 the spot might be a reclaimed marsh, and that this plant is the remains 

 of the marsh vegetation, and hence its starved appearance. This I do 

 not think at all likely ; the appearance of the ground seemed to me to 

 preclude the possibility of its ever having been a marsh or anj-thing 

 approaching one, being, as I have said, on a hill of considerable height, 

 and of a diy soil ; and, moreover, the plant was in gi-eat abundance 

 growing amongst the wheat. Perhaps some reader of the "Midland 

 Naturalist " can give some explanation. The last observations I made 

 were at Shuckburgh, viz., Conium ninculutum, Circaa lutetiana, and 

 remai'kably luxuriant forms of Braehij podium si/lraticum, attaining, I 

 should say, over 4ft. in height. — H. W. Teott, llugby. 



The Eoyal Oak at Boscobel. — In the report of the excursion of the 

 Shropshire Archcoological and Natural History Society, in the last 

 number of the " Midland Naturalist," the age of the tree now shown as 

 the Royal Oak is discussed. It is said that in 1857 its girth was lift. 4in. 

 at 4ft. from the ground. I have counted the I'ings and measured the 

 average rate of growth of a good many trees of various kinds, and have 

 adopted as a rough but fairly accurate estimate of the age of oaks, that 

 every foot diameter represents about fifty years of gi'owth. The increase is 

 greatest in middle hfe. The annual ring of wood is never less that iV of 

 an inch thick, and not often more than | inch. Taking the average as | aU 

 round the trunk, the diameter would increase J inch annually, or a foot 

 in forty-eight years. A tree lift. 4in. in girth is 3ft. 9.',in. in diameter, 

 which according to this calculation would represent about 180 yoai's of 

 gi'owth. But the tree in which the King took shelter must have been in 

 1857 about 250 years old. The rapidity of growth is affected by soil and 

 climate, and I do not know the soil of Ijoscobel. If it is poor and shallow 



