qually important on occasion to examine
the tissues of adult specimens, and for this, as a rule, the tissues
must first be subjected to some preserving and hardening process
preliminary to the cutting of sections for microscopical examination.
This is done simply enough in the case of some organisms, but there is
a large class of filmy, tenuous, fragile creatures in the sea population
of which the jellyfish may be mentioned as familiar examples. Such
creatures, when treated in an ordinary way, by dropping them into
alcohol, shrivel up, coming to resemble nothing in particular, and
ceasing to have any value for the study of normal structures. How to
overcome this difficulty was one of the problems attacked from the
beginning at the Naples laboratory. The chief part of the practical work
of these experiments fell to the share of Signor Lo Bianco. The success
that attended his efforts is remarkable. To-day you may see at the
laboratory all manner of filmy, diaphanous creatures preserved in
alcohol, retaining every jot of their natural contour, and thus offering
unexampled opportunities for study _en masse_, or for being sectioned
for the microscope. The methods by which this surprising result has been
accomplished are naturally different for different creatures; Signor Lo
Bianco has written a book telling how it all has been done. Perhaps the
most important principle involved with a majority of the more tenuous
forms is to stupefy the animal by gradually adding small quantities of
a drug, such as chloral, to the water in which the creature is detained.
When by this means the animal has been rendered so insensible that
it responds very sluggishly to stimuli, it is plunged into a toxic
solution, usually formaline, which kills it so suddenly that its muscles
in their benumbed state have not time to contract.

Any one who has ever tried to preserve a jellyfish, for example, by
ordinary methods will recall the sorry result, and be prepared to
appreciate Signor Lo Bianco's wonderfully beautiful specimens.
Naturalists have come from all over the world to Naples to learn "just
how" the miracle is accomplished, for it must be understood that the
mere citation of the _modus operandi_ by no means enables the
novitiate to apply it successfully at once. In the case of some of the
long-drawn-out forms of clustered ascidians and the like, the delicacy
of manipulation required to make successful preservations raises the
method as practise