THE MARINE AQUARIUM. 69 
CHAPTER IV. 
THE PLANTS. 
As already stated, the green weeds are most suitable, 
the red next so, but of the brown and olive sorts there 
are very few that can be kept in a state of health for any 
length of time. There are only two plants suitable 
for the commencement of the experiment, and these are 
Ulva latissima, the common sea lettuce, and L:nteromorpha 
compressa, a delicate grass-like alge, of a very cheerful 
green. Of these Mr. Lloyd and Mr. Hall have always 
plenty on hand, ready cleaned and prepared for immediate 
submersion. Artificial water soon acquires the properties 
of natural sea water under the influence of these plants, 
which grow rapidly, and disseminate their spores through- 
out the tank, at the same time giving abundance of 
oxygen for the support of animal life. 
When a few weeks have elapsed Chondrus crispus, 
better known.as “‘ Carrageen moss,” may be added, it is a 
free grower found in plenty on the ledges at extreme low- 
water mark. The green weeds Codium tomentosum, Cla- 
dophora arcta, and rupestris, and Bryopsis plumosa may 
be considered safe stock when the water has been in use a 
month or two, but the growth of the more delicate of the 
Rhodosperms must not be attempted in artificial water for 
at least three or four months. 
The best weeds of the latter class are Phyllophora 
rubens, Corallina officinalis, and Iridea edulis. In col- 
lecting, no doubt the Dulse, Delesseria alata, and san- 
eee 
