1 96 THE MARSILIAS. 



flora. From the original station plants have been sent 

 to many other places, and in each they have grown 

 luxuriantly, vying with the natives in their ability to 

 hold their territory and to gain more. The pretty 

 oxalis-like leaves resting upon the water or rising a short 

 distance above it may be counted as an addition to our 

 lakes and ponds, while the ease with which it may be 

 grown makes it a general favourite. It may even be 

 grown in a tub in the back yard, and is often seen in 

 conservatories. 



In its native haunts Marsilia quadrifolia usually roots 

 in the mud beneath shallow water, the very slender 

 rootstock, a yard or more long, creeping above the soil 

 and sending up. great numbers of leaves on slender 

 petioles that elongate until they reach the surface. 

 While this is the usual habitat, it may often be found 

 quite out of water at midsummer. The leaves are 

 then quite short, but such plants are usually very fruitful. 

 The joints of the stem are short, and from each is pro- 

 duced a tuft of roots and a leaf. In the bud these 

 leaves are coiled and the four divisions folded together, 

 but as they reach the air they unfold and spread out on 

 the water like the leaves of the water-lily. In vigorous 

 specimens the petioles often hold the young leaves 

 above the water. In outline the blade is nearly circu- 

 lar, from half an inch to two inches or more in diam- 

 eter, and is divided into four equal leaflets, wedge-shaped 

 at base and rounded on the outer margins. The divisions 

 are marked by numerous fine veins that run from the 

 petiole to the margin, forking several times. The young 

 leaves are more or less hairy, but when full grown they 

 are smooth. 



The pporocarps are about half the size of peas and nre 



