How to obtain it. 97 
water. Shell fish deposit their spawn freely upon its leaves. Of 
all plants, the lakewort and the water lobelia are, I think, two of 
the most suitable for introduction into trout ponds. The latter 
was named in honour of the Flemish physican, Matthias de Lobel, 
who was botanist to James I. 
The great water moss (/ontinalis antipyretica) is a valuable 
plant, and delights in rocky streams and raceways. It also does 
well in ponds where there is a good current, and grows chiefly 
on stones, though it may often be found in streams growing on 
wood or tree roots, and I have found it growing freely on gravel 
beds in lakes. It is very useful in providing a good shelter for 
trout, and also as in insect producer, and in raceways is 
invaluable. One great advantage is that it does not grow with 
sufficient luxuriance to choke places up as some plants do, and it 
is easily thinned out if desirable. It can be introduced by 
planting stones on which specimens are growing, or by placing 
tufts of it in the gravel. Planting in raceways and streams is 
easily done by simply fastening a stone on to the root of the plant 
and pressing it into the bottom. 
In addition to the great water moss, the starwort (Cal/itriche ) 
and water crowfoot (Ranunculus aquatilis) are useful in streams. 
The latter sometimes becomes a pest when it gets into ponds. It 
is needful, therefore, to use care in introducing it into pond or 
lake tributaries, and the same applies to some other plants. The 
milfoil (Afyriophyllum ), for instance, is an excellent plant in many 
streams, but in ponds it isa perfect pest. When it occurs in a 
stream which feeds a pond, the seeds or small portions of the 
plant itself will inevitably float down into the pond and grow. 
Some of the Ranunculacee are exceedingly acrid and have been 
used for producing blisters, but the wounds made proved very 
troublesome and difficult to heal. Ranunculus flammula already 
referred to is one of these, though in trout ponds it does not 
seem to be injurious but rather the reverse. The water celery or 
celery-leaved crowfoot (2. sceleratus) I have carefully avoided, as 
well as some others of the genus, on account of their acrid 
tendencies. 
The bladderwort (Utricularia vulgaris) has been found to 
eat fish, or at least to destroy them. This discovery was made by 
H 
