156 THE ECHINODERMS OF TORRES STRAIT. 
live in the open not uncommonly occur by dozens on a relatively small area. As 
sluggish as sea-urchins, and absolutely without means of escape, holothurians are 
the easiest of echinoderms to capture. They have no means of defense except the 
very sticky Cuvierian organs of a few species and these organs are harmless, state- 
ments to the effect that they are poisonous or irritating to the touch being absolutely 
wrong. Their sliminess and stickiness are unpleasant, but perfectly harmless, at 
least to human beings. 
Most holothurians are quite sensitive to staleness of the water in which they 
are placed, and many species, especially in the genera Stichopus and Holothuria, 
tend to disintegrate as the freshness of the water is lost. Whether this is due to 
lack of oxygen or to excess of Cos, or to some other factor, has never been deter- 
mined. The process begins by the softening and sloughing off of bits of the epider- 
mis. These areas rapidly increase in extent and the underlying tissues of the body- 
wall begin to assume a mucilaginous consistency, until at last the body-form is 
lost and the whole animal is a shapeless mass of semisolid slime. The same process 
often goes on if the animal is simply laid on a rock out of water. This sensitiveness 
to the condition of the water necessitates care in collecting specimens; the buckets 
in which they are placed must not be overcrowded and the holothurians should be 
killed as soon as may be. Since they are very contractile, and in particular retract 
their tentacles completely when disturbed or handled, good specimens can, as a 
rule, be secured only by narcotizing before killing. Holothurians are very suscep- 
tible to Epsom salts (MgSO,) and relax more or less completely after a time when 
placed in a saturated solution thereof. Some species of Cucumariide will not 
re-expand the tentacles, even when narcotized, but by carefully exerted pressure 
and suitable manipulation, those organs can usually be forced out into a relatively 
extended condition. ' 
BECHE-DE-MER. 
One of the practical results that it was hoped to secure from the study of Torres 
Strait holothurians was the accurate identification of the species used for béche- 
de-mer. It was thought possible that specimens secured from the dealers, given 
the right treatment in the laboratory, might be identifiable. Such proved to be 
the case, but unfortunately it immediately appeared that trade names have little 
relation to specific characters, and several species may appear under a single trade 
name, or the reverse may be true, several trade names being applied to a single 
species. It was noted that different men applied the trade names in different 
ways, and I was unable to determine whether this was due to lack of knowledge 
or to a general looseness in the use of the trade names. The various trade forms 
that were secured are as follows, the scientific name of the species concerned being 
given in connection with it. All belong to the family Holothuriide. 
“Goop FisH”’: 
Prickly-red fish, Thelenota ananas. Mammy fish, Actinopyga nobilis. Teat fish, A. nobilis. 
Red fish, A. mauritiana. Black fish, A. miliaris. 
“CHEAP FisH”’: 
Stone fish, Actinopyga lecanora. Sand fish, Holothuria marmorata, H. scabra. Chalky fish, 
H. marmorata. Curry fish, H. scabra, Stichopus variegatus?. Lolly fish, H. atra. Tiger 
fish, H. argus. 
