VARIOUS SOFT-BODIED INVERTEBRATE ANIMALS. 107 
removed from this mixture the moment they are killed, since the acid 
will quickly attack the calcareous spicules, which are important for 
the identification of the Alcyonaria, and placed in 35 per cent, or 
50 per cent, alcohol ; it is well to inject the alcohol into the mouths 
of the polyps to keep them fully expanded. The preparation should 
finally be preserved in 70 per cent, alcohol. 
Regarding the Sea Anemones, no definite rule for preservation 
can be given. Much of the success of the preparation depends on 
the form employed, some species contracting much less readily and 
less perfectly than others. Some may be killed in a fair condition 
by pouring over them boiling corrosive sublimate, and then, before 
consigning them to alcohol, treating for a few minutes with 
0*5 per cent, chromic acid. 
Stony Corals should be allowed to expand fully, and should then 
be killed with boiling solution of corrosive sublimate and acetic acid 
used in volume equal to that of sea-water containing the coral. 
The colony should then be transferred to 35 per cent, alcohol, some 
of this fluid being, if possible, injected into the mouth of each 
polyp. The injection should be repeated at every change of the 
alcohol, and the specimens should be preserved in 70 per cent, 
alcohol, after washing them well in iodized alcohol. 
Professor Hickson writes, in reference to the Alcyonarian Corals, 
as follows : — All Stolonifera, including Tubipora, preserve well in 
spirit. Tubip>ora and some of the large Clavularias, however, hold 
in their cavities a large amount of sea-water, and consequently the 
spirit in the bottle soon becomes weak, and must be changed once 
or twice. 
The only satisfactory way of killing Tubipora expanded is to throw 
a concentrated solution of corrosive sublimate on to a colony when 
expanded in a shallow pool on the reef ; but if expanded colonies are 
removed as rapidly as possible from their position and plunged into 
strong spirit, the polyps are killed partially expanded in a manner 
useful for investigation. 
Thick coriaceous Alcyonarians, like Alcyonium or Sarcopliytum, 
are capable of contracting so tightly that spirit and other preserva- 
tives fail altogether to penetrate their tissues, unless special care 
be taken. Nearly all specimens taken from a dredge and placed 
