102 ENGLISH BOTANY. 



This plant is very common in our streams and ditclies, and is the one against 

 •which so much caution is given lest it sliould be mistaken for watercress. It is 

 usually known by the name of Slum nodijlorum, and was at one time admitted into 

 the London Pharmacopreia as an antiscorbutic. Dr. Withering speaks of it as a 

 valuable remedy, and mentions the case of a young lady whom he cured of a cutaneous 

 eruption, by giving her three large spoonfuls of the juice twice a day mixed in milk, 

 lie affirms that in this way it produces no unpleasant results. It would appear, 

 therefore, that if at any time eaten by mistake for watercresses, it need cause no 

 alarm as to any serious consequences ensuing. A little knowledge and care will, 

 however, prevent any such mistake being made, if it be remembered that the leaves 

 of the UiiibelliferjB, to which the objectionable plant belongs, aiways sheath at their 

 base. It is often called Fool's Watercress. 



SPECIES II.— HELOSCIADUM INUNDATUM. Koch. 



Plate DLXXV. 



Reich. Ic. Fl. Germ, et Helv. Vol. XXI. Tab. 1855. 

 nillot, Fl. Gall, et Germ. Exsicc. No. 2G79. 

 Apium nodiflorum, Reich. Jil, Ic. Fl. Germ, et Helv. p. 10. 

 Sison inundatum, Linn. Sm. Eng. Bot. No. 227. 



Stem floating or decumbent, rooting at the lower nodes. Lower 

 leaves bi- or tri-pinnate, with the ultimate segments setaceous, 

 rarely linear; upper leaves pinnate, with 2 to 6 pair of pinnae; 

 leaflets wedgeshaped or rhomboidal, attenuated towards the base, 

 pinnatifid or deeply cut. Umbels opposite the leaves, shortly 

 stalked; rays generally 2, but from 2 to 4, unequal. Ijivolucre 

 none ; involucel of 3 or 4, rarely 5 or 6, lanceolate 3-nerved her- 

 baceous leaves. Cremocarp longer than broad. 



In ponds and wet places, by the sides of lakes. E/ather rare, 

 but generally distributed. 



England, Scotland, Ireland. Perennial. Summer. 



A small inconspicuous plant, with stems 3 inches to 1 foot 

 long. Submerged leaves divided into capillary segments some- 

 what resembling those of the Batrachian Ranunculi, the upper 

 leaves and flowers rising out of the water : these leaves have 

 broad sheathing petioles and rather distant leaflets, the lowest 

 pair, especially, remote from the others, i to J inch long, more 

 deeply incised or divided than in II. nodiflorum. Umbels on stalks 

 •J to 1 inch long, usually of 2 divaricate rays, the longest i to ^ inch 

 long. Flowers very minute, with the petals oval, flaccid, entire, 

 and slightly incurved at the point. Cremocarp ^ inch long, brown, 

 with the ribs paler, broad and very prominent. Styles very short, 

 recurved. Plant greeii, glabrous. 



Dr. D. Moore finds in the river Boyne, co. Cavan, a very lux- 

 uriant form, which is nearly as large as H. nodiflorum, and has the 



