CLASS V. ORDER 11. J HYDROCOTYLE. 347 



CENUS XLVI. HYDROCOTYLE.— Linn. Whiterot. 



Gen. Char. Calyx margin obsolete. Petals ovate, entire, acute, with 

 a straight point. Fruit compressed at the sides, so as to form two 

 flat nearly orbicular lobes. Carpels with five filiform ridges, those 

 of the sides and back nearly obsolete, and the two intermediate 

 ones arched. Seeds carinated, compressed. — Name from v^w^, 

 water ; and xotiAj?, the cotula, or cup, from the shape of the 

 leaves being depressed on the centre stalk, and somewhat re- 

 sembling a cup. 

 1. H. vulgaris, Linn. (Fig. 411.) common. Whiterot, Marsh Penny- 

 wort. Leaves peltate, orbicular, somewhat lobed and crenated ; 

 umbel of about five nearly sessile flowers. 



English Botany, t. 751.— English Flora, vol. ii. p. 96.— Hooker, 

 British Flora, vol. i. p. 126. — Lindley, Synopsis, p. 128. 



Stem very long, filiform, creeping on the surface, and putting out 

 from the joints numerous fibrous roots, and from the same point one, 

 but mostly numerous leaves and flowering stems, quite smooth, suc- 

 culent, pale green, or pinkish, simple or branched. Leaves on long 

 slender simple upright footstalks, from two to three inches long, smooth, 

 or scattered over with a few fine hairs, orbicular, shield-like, with the 

 footstalk from the centre, from whence radiate around the branched 

 veins more or less prominent on the under side, the margin more or 

 less lobed and crenated, quite smooth, light green, horizontal. Flower 

 stalks simple, slender, seldom more than an inch long, arising from the 

 axis of the leaves, with a pair of small hractea at the base, bearing at 

 its extremity one, sometimes two, one above the other small umbels, of 

 about five flowers, on very short footstalks, with an involucra of four 

 or five segments at the base. Flowers small. Calyx without limb. 

 Petals broadly lanceolate, white, or frequently with a pinkish tinge, 

 entire, spreading. 



Habitat. — Bogs and low wet meadows ; frequent. 

 Perennial ; flowering in May and June. 



Hydrocotyle, common water cup, marsh pennywort, whiterot, flowk- 

 wort, or sheep killing pennygrass, is very common in wet marshy 

 places, growing amongst the grass ; and it has received its last name 

 from the popular belief that it is the cause of that destructive 

 disease of the liver in sheep, known by the name of rot. Why 

 such an opinion should have become general we are at a loss to 

 imagine, for if the promulgators of this idea had observed the sheep 

 with greater attention, it would have been found that they will not 

 eat this plant. It is true that in sheep kept in wet meadows where 

 this plant grows, the disease is developed ; but if the occupiers of these 

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