Aug. 24, 1888.J 



SCIENTIFIC NEWS. 



i8r 



THE BOTANY OF BRISTOL— I. 



"C*OR natural history purposes the neighbourhood of 

 Bristol may fitly be considered co-extensive with 

 the area of the Bristol coal-fields as defined in the geolo- 

 gical map of Mr. Sanders. A district thus limited has 

 already been adopted by local entomologists, geologists, 

 and botanists, in portraying the Bristol features of their 

 respective branches of science ; and to the student it is 

 an undeniable advantage to carry on field work of this 

 kind within boundaries which are substantially natural, 

 instead of drawing an entirely arbitrary line around the 

 city taken for a centre. We speak of the Bristol district, 

 therefore, as bounded on the west by the Severn and the 

 Bristol Channel ; on the south by the river Brue, which 

 tails into the mouth of the Parrett, jnst below Burnham ; 

 and as extending north to the town of Berkeley, and east 

 to the cities of Bath and Wells. Portions of North 

 Somersetshire and of West Gloucestershire are included 

 in this area, and are separated, save for a short distance, 

 by the river Avon, which, passing through Bath and 

 Bristol, joins the Severn at Avonmouth. Obviously we 

 have here an extensive tract of country to work over. 

 However, one may justly say that every part of it is not 

 only of great interest to the naturalist, but is easily ac- 

 cessible from Bristol. In these days facility of locomotion 

 is so great that a run often or fifteen miles out and home 

 is within the reach of anyone who has half a day to spire. 

 By rail, by cycle, or by " Shanks's pony " (and the field 

 botanist being essentially a pedestrian will commonly 

 prefer the latter) every portion of the district can be 

 reached and explored without undue fatigue or an unen- 

 durable tax upon a slender purse. Moreover, our chief 

 botanical wealth lies in the immediate neighbourhood of 

 the city, where, upon St. Vincent's Rocks and on the 

 Downs, in the Avon Gorge, Leigh Woods, or the Frome 

 Valley, the stranger who visits Bristol in search of plants, 

 while rambling amid delightful scenery, will become ac- 

 quainted with many of the greater rarities. Before 

 mentioning these plants in detail it will perhaps be well, 

 for the benefit of readers unfamiliar with the country, to 

 give a brief topographical sketch of its natural features 

 and surface condition. 



The city of Bristol lies in a somewhat triangular basin 

 at the confluence of the rivers Avon and Frome, 

 the latter a small tributary from the north-east, which 

 flows through the picturesque Glen Frome, and is not to 

 be confounded with the larger stream passing by the 

 town of that name. Around the city arise hills which 

 are more or less broad tablelands or plateaux. The 

 steep acclivities on the north are beds of carboniferous 

 limestone and millstone grit. To the south the swelling 

 slopes of Knowle and Totterdown extend to Dundry 

 Hill, which rises to 769 feet above mean sea level. 

 Solid Jurassic beds are the cause of the existence of this 

 high ground, which bounds the horizon for a considerable 

 sweep. On the east of the city there is an irregular 

 elevation, with an average height of about 180 feet. This 

 extends from the river Frome on the north-east to the 

 cliffs which bound the Avon byConham and Brislington, 

 and consists for the most part of coal measures, contain- 

 ing the sites of numerous coal-pits. It is the hard 

 Pennant sandstone of the coal period, which is cut 

 through by the Avon in the picturesque winding of the 

 river by Conham. The influence of the tide is shut off 

 near this point, and the river being locked becomes a 

 canal joining the Kennet and Avon system, and forming, 

 before the development of railway traffic, one of the 



most important links of inland navigation between 

 Bristol and the Metropolis. Travelling eastward, the 

 riverside scenery and botany change to the commonplace, 

 and from the Pennant valley to Bath do not invite our 

 special attention. In its tidal course to the Severn below 

 Bristol the river passes by the Hotwells, under Clifton 

 and St. Vincent's Rocks, and onward between the cliffs 

 and quarries of the Avon Gorge. Lower down it passes 

 through an extensive tract of alluvial flats drained by 

 numerous intersecting ditches, chiefly brackish. These 

 abound with algae and other interesting matter for in- 

 vestigation. Small brooks, draining respectively Bed- 

 minster Meads and Ashton Marshes, with the meadows 

 behind Long Ashton, flow into the Avon at Bedminster 

 and Rownham. Other principal sources of drainage in 

 the district are the Chew, the Trym, and the Axe. The 

 former runs through rich pastures between Dundry 

 and the Mendips, by way of Chew Magna and Stanton 

 Drew, falling into the Avon near Chewton Keynsham. 

 Most excellent botanizing is to be had throughout i's 

 course. 



Either on the banks of the Chew or on ground rising 

 from them a number of good plants may be gathered, 

 including Helkborus viridis, Viola odorata, V. alba, V. 

 Rcichenbachiana, Saponaria officinalis, Stellaria umbrosa, 

 Rubus silvaticus, R. Radula, Rosa subglobosa, Epilobiuin 

 roseum, Senccio saracenicus in profusion, Inula Heknium, 

 Mentha sylvestris, M. piperita, Polygonum Bistorla, Daphne 

 Laureola, Sa/ix alba, and the barren plant of S. fragilis, 

 which is unknown elsewhere in the district ; Popu/us 

 canescens, P. tremula, Orchis latifolia (type), Juncus com- 

 pressus, Calamagrostis Epigejos, Clyceria plica/a, Polysti- 

 chum aculeatiim, and P. angulare. 



The Trym is a smaller stream of less importance. It 

 collects the drainage from the high lands about Henbury, 

 and passing through Westbury and Coombe Dingle, falls 

 into the Avon at Sea Mills, amid a submaritime marsh 

 flora. 



Besides the already mentioned Dundry, there are in 

 the vicinity of Bristol some isolated hills of an altitude of 

 from 250 to 300 feet. But the chief elevations are on 

 the great Mendip range, a few miles to the south-east, 

 and among the southern spurs of the Cotswolds, which 

 come down into the north-eastern portion of the area as 

 far as Wotton-under-Edge. The latter afford some 

 enjoyable rambles from stations on the Midland Railway, 

 being sometimes wooded, and their slopes sprinkled with 

 abundance of belladonna, lily of the valley, Polygonatum 

 officinale, and good orchids ; or open and grassy, flecked 

 with patches of Hippocrcpis, Trifolium medium, Rosa 

 tomentosa, and Brachypodium pinnalum. This grass has 

 foliage of a bright yellowish-green colour, contrasting 

 strongly with the brown hue of the turf around, and 

 rendering the spots where it grows conspicuous at a long 

 distance. 



The Mendip Hills are, for the most part, huge masses 

 of limestone, rocky and precipitous in places, but chiefly 

 consisting of rough pasture and rugged slopes, presenting 

 to-day the same features and appearance that they did 

 when Roman miners delved and pitted their surface 

 in the search for ore. The levels vary up to the top 

 of Black Down, a wide expanse of elevated open moor 

 and heath rising to an altitude of over 1,100 feet. The 

 only true bog we possess occurs upon this range. In 

 consequence, we find on Mendip several paludal species 

 that are unknown or uncommon elsewhere about Bristol ; 

 for example, Viola palustris, Peplis Portula, Scutellaria 



