BOTANY CHENOPODIACE/B LILIACE./E Chenopodium ficifolium, Sm. FritiUaria meleagris, L. glaucum, L. AROIDE./E POLYGONACE^E Acorus calamus, L. Polygonum maculatum, Dyer et Trimen ALISMACE Rumex palustris, Sm. (limosus, Thuill.') Damasonlum stellatum, Pers. DISTRICT VI. THE LEA The Lea district is the largest, comprising the whole of the eastern portion of the county south of the Cam and Ivel districts. It is bounded on the south by Middlesex, on the east by Essex, on the north by the Cam and Ivel districts, and on the south-west by the Colne district. A small portion of the county on the north of the Colne district and having Bedfordshire for its northern boundary drains into the head of the Lea ; * and another small area on the east of the Brent district is drained by a tributary of the lower portion of the Lea, now however flowing into the New River. The Lea rises in Bedfordshire from springs in Leagrave Marsh three miles above Luton ; cuts through the Chalk escarpment before it enters Hertfordshire ; and flows past Hatfield, Hertford, Ware, and several towns in the south-east corner of the county. After receiving on its left bank several streamlets whose waters are lost in the Chalk in dry weather, it flows to Hertford, where the Mimram and then the Beane join it, and from this point downwards it is navigable for barges ; the Rib adds its tribute between Hertford and Ware, the Ash below Ware, and finally the Stort a little above Hoddesdon. All these rivers flow into the Lea on its north or left bank. The Mimram, or Maran, rises in Lilley Bottom near King's Walden and flows past Welwyn and through many beautiful parks. The Beane, or Bene, formerly called the Benefician, is formed by numerous small streams rising between Sandon and Weston, and is augmented at Walkern from springs in the Chalk, at Frogmore above Watton by a brook from Stevenage and Knebworth, and in Woodhall Park below Watton by the Munden Brook, dry in summer. The Rib rises in Kelshall Woods near Therfield, or in very dry years some miles lower down its valley, passes Buntingford, and a few miles below it receives the Quin, which rises at Rushing Well near Nuthamstead, and is often dry in summer as far as Braughing. The Ash rises in the winter near Brent Pelham on the borders of Essex, but for five miles down its valley it and its tributary streams are merely bournes, being dry in the summer and autumn, and its source is then a mile below Albury, where there is a spring in its bed, below which it is seldom dry. The Stort is the only affluent of the Lea, except a few small brooks below Hoddesdon, which does not entirely flow through Hertfordshire. Rising near Clavering in Essex, but having one of its tributary streams flowing from Scales Park Wood in Herts near the source of one of the feeders of the Quin, it comes into our county for a run of a quarter of a mile, then re-enters Essex, and enters Herts again at Pesterford Bridge, two miles above Bishop Stortford, from which point to its junction with the Lea it is navigable for barges and is called the ' Stort Navigation.' Here it serves as boundary between Herts and Essex. In addition to the supply from these tributary streams, the waters of the Lea are augmented on its left bank by the springs of Arkley Hole at Woolmers, and on its right bank by the Chadwell Spring between Hertford and Ware. This spring first dried up in 1898, and has done so in each succeeding year. Between Ware and Hoddesdon the Lea was formerly augmented by Amwell Spring (Emmewell or Emma's Well), but this seldom flows now, having been pumped dry by the New River Company. The Chadwell Spring is fast following in its footsteps, and Arkley Hole is also being affected. In course of time this lowering of the plane of saturation of the Chalk will affect the surface- soil and alter the character of the flora of this district. The Chadwell Spring for many years has formed the head of the New River, into which also the Amwell Spring was diverted when this water-channel was constructed. The Lea leaves the county at Waltham Cross for Middlesex, and flows into the Thames at Bow Creek below Blackwall. It is tidal as far as Lea Bridge. Below Ware the course of the Lea has been diverted for navigable purposes, and the ' Lea Navigation ' to its junction with the Stort, and ' Lea and Stort Navigation ' below this point, cross and re-cross the old bed of the Lea several times. 1 In the recent revision of the county boundary for administrative purposes this portion has been transferred to Bedfordshire. 57
