Marc 31, 1904] 
IA TORE 
ee 
Familiy Bacteriaceae. Cylindrical forms, ciliated. 
(1) Genus Bacillus. Forms with peritrich cilia. 
(2) Genus Pseudomonas. Forms with polar cilia. 
It cannot but be interesting to medical bacteriologists to 
learn that the pathogenic Streptococci are motile. At the 
conclusion of the third paper the exact method by which 
successful cilia preparations can be obtained is given. 
FLUORESCENT BODIES EXCITED BY 
RADIUM. 
SINCE very active preparations of radium have become 
available, a steady search has been going on in many 
quarters for agents which will respond to the radiations 
and convert them into visible light. The most powerful 
fluorescer towards the a radiations is Sidot’s hexagonal 
blende, a crystallised form of zinc sulphide, which is especially 
suited for use with the emanation. The most powerful to 
the B radiation is willemite, a zinc silicate, which gives 
a magnificent green fluorescence, and is probably quite 
free from any phosphorescence after the action of the rays 
ceases. This if left in the radium emanation steadily in- 
creases in brightness as the excited activity, and with it 
the 8 radiation, is produced, and reaches its maximum some 
hours after the emanation has been introduced. The same 
is true of kunzite, a new variety of spodumene discovered 
by Dr. Kunz, and supplied by Messrs. Griffin and Sons, 
Ltd. The colour of the light might be variously described 
by different observers as salmon-pink, warm orange, or 
orange-yellow, according to individual opinion. Kunzite is 
a transparent gem-like crystal, and is one of the most 
beautiful examples of the fluorescent bodies at present avail- 
able for demonstrating the luminous effects produced by the 
radium rays. It is, however, not very powerful compared 
with willemite or the platinocyanides. Being, like the 
diamond, transparent, it shines especially well when ex- 
posed in a tube to the action of the concentrated radium 
emanation, as the whole mass of the crystal contributes to 
the light effect. The growth of the luminosity after the 
emanation is introduced, owing to gradual production of 
the excited activity, is more marked than in the case of 
willemite, as kunzite hardly seems to respond at all to the 
a radiation. This experiment would be instructive as a 
lecture illustration to prove that the emanation only gives 
a rays, and that the 8 rays are produced only when time has 
been allowed for, some of the emanation to change into the 
matter causing the excited activity. 
The most brilliant and exquisite of all fluorescers for 
demonstration on a large scale are the platinocyanides in 
the form of large crystals. Those containing lithium give 
a beautiful pink, not unlike that of kunzite, but more 
brilliant. The colour of the latter is doubtless due to the 
lithium contained in it. The calcium and barium salts are 
characterised by a deep green, especially the former, whereas 
the sodium compound shines lemon-yellow. Magnesium 
platinocyanide, which is so beautiful under the X-rays, 
hardly responds at all to radium. The feeble y rays are 
best shown by a large crystal of the barium or lithium 
salt. Large crystals of the platinocyanides seem extremely 
difficult to obtain, and any manufacturer who could produce 
them would probably find a ready market. 
A new fluorescent mineral, which, like kunzite, seems 
to respond only to the B rays of radium, has been recently 
discovered by Mr. Armbrecht, a member of the firm of 
Armbrecht, Nelson and Co., chemists, Duke Street, W. 
The mineral is sparteite,-a form of calcite containing a few 
per cent. of manganese. It occurs associated with willemite 
and with zincite, the red oxide of zinc, which contains a 
trace of manganese. It is pure white in colour, and under 
the action of the 8 radium rays fluoresces a very deep orange. 
The light is not at all powerful, but the colour is very re 
markable, and would excite comment merely as a fluorescent 
phenomenon without reference to the way in which it is 
produced. One authority described it as exactly similar to 
the colour given by neon in a spectrum tube. It is rather 
remarkable that the colour seems to depend on the intensity 
of the rays, and is of a deeper tint when the radium is held 
near than when it is removed a short distance. ~The same 
NO. 1796, VOL. 69] 
gentleman has discovered among the fluorites some examples 
of phosphorescence after exposure to radium which persist 
for several days, and exhibit marked increase of brilliancy 
on exposure to the warmth of the hand. He finds that 
kunzite exhibits a similar behaviour, the after phosphor- 
escence (or thermo-luminescence?) being notably increased 
if the mineral is held in the hand. 
‘The action of kunzite and sparteite under the kathode 
rays is of interest. In each case the colour is considerably 
different from that under the action of radium, being much 
yellower. Sparteite under these conditions is disappointing, 
but kunzite is a most beautiful sight. Its colour is a pure 
deep yellow without a trace of the warmth it exhibits under 
radium. BS: 
THE PALOLO WORM OF SAMOA. 
“THE periodical autumnal swarming in the seas around 
the Samoan Islands of the annelid locally known as 
the palolo has attracted the attention of residents in those 
islands and naturalists generally for many years. The 
swarming takes place in October and November, apparently 
on the day before the last quarter of the moon, and on this 
and the following day the sea is absolutely alive with the 
worms, of which the numbers seem to be greater in the 
November than in the October swarm. Early dawn is the 
time for the swarming to commence, and by sunrise the 
phenomenon is at its height. Not the least curious feature 
about the swarming is the fact that all the worms are im- 
perfect and headless, and the nature of the complete worm 
has long been a puzzle to naturalists. Thanks, however, to 
the investigations of Messrs. Kramer and Friedlander, sup- 
plemented by the observations of Mr. W. McM. Woodworth, 
the solution of the problem has at length been discovered. 
The results of these investigations have been published in 
Dr. Kramer’s ‘‘ Die Samoa Inseln’’ (Stuttgart, 1903), 
while the original English version of this account, drawn 
up by Mr. Woodworth, appears in the American Naturalist 
for December last. 
Palolo also occur in Fiji and elsewhere. 
annelid—Eunice viridis—burrows into the 
Samoa, the reef, when prised 
open with a crowbar, proving 
shortly before the swarming 
season to be absolutely alive 
with palolo. Curiously 
enough, the Samoan natives, 
although familiar with the 
palolo when swarming, are 
quite unacquainted with it 
during the period of its rock- 
boring existence. Owing lo 
the great length of the entire 
worm, its fragile structure, 
and its intricate association 
with the honeycombed reef, 
the extraction of complete 
specimens is a matter of con- 
siderable difficulty, demanding 
very delicate manipulation on 
the part of the operator. 
The complete annelid con- 
sists of two distinct parts, a 
broad anterior ‘* atokal ’’ por- 
tion, sharply marked off from 
a slender and much longer 
‘* epitokal ’’ portion, which at 
the swarming season becomes detached and constitutes the 
free-swimming palolo. The total length averages 40 centi- 
metres, of which about the first fourth is formed by the 
thick atokal portion. From 250 to 430 is the approximate 
number of segments in the atokal region, the smaller 
number occurring in a female and the larger in a male. 
In the males the colour is reddish brown, and in the females 
bluish green. These sexual colours are most strongly 
marked in the epitokal region, where they are due to the 
sperm and ova, the collapsed integument being quite colour- 
less after the discharge of those elements. 
Palolo, as above mentioned, are by no means confined to 
Samoa. ‘‘ A similar swarming of marine annelids,’’ writes 
The complete 
reef-rock of 
Fic. 1.—Eunice viridis (Gray). 
The narrow posterior epitokal 
part when detached and free- 
swimming is known as the 
“*Palolo.” 
