anon they rose till they hung above the trees； apparently having
no forward or horizontal motion except when taken by the gentle
breeze； merely sinking and rising。
〃How pretty they are！〃 said Cortlandt； as they watched them。
〃For bodies consisting of marsh gas； they hold together
wonderfully。〃
Presently one alighted on the water near them。 It was
considerably brighter than any glow…worm； and somewhat larger
than an arc lamp； being nearly three feet in diameter； it did not
emit much light； but would itself have been visible from a
considerable distance。 Cortlandt tried to touch it with a
raft…pole； but could not reach far enough。 Presently a large
fish approached it； swimming near the surface of the water。 When
it was close to the Jack…o'…lantern； or whatever it was； there
was a splash； the fish turned up its white under side； and； the
breeze being away from the raft； the fire…ball and its victim
slowly floated off together。 There were frequently a dozen of
these great globules in sight at once； rising and descending； the
observers noticing one peculiarity； viz。； that their brightness
increased as they rose； and decreased as they sank。
About two and a half hours after sunset； or midnight according to
Jupiter time； they fell asleep； but about an hour later Cortlandt
was awakened by a weight on his chest。 Starting up； he perceived
a huge white…faced bat； with its head but a few inches from his。
Its outstretched wings were about eight feet across； and it
fastened its sharp claws upon him。 Seizing it by the throat； he
struggled violently。 His companions； awakened by the noise；
quickly came to his rescue； grasping him just as he was in danger
of being dragged off the raft； and in another moment Bearwarden's
knife had entered the creature's spine。
〃This evidently belongs to the blood…sucking species；〃 said
Cortlandt。 〃I seem to be the target for all these beasts； and
henceforth shall keep my eyes open at night。〃
As day would break in but little over an hour； they decided to
remain awake； and they pushed the dead bat overboard； where it
was soon devoured by fishes。 A chill had come upon the air； and
the incessant noise of the forms of life about them had in a
measure ceased。
Cortlandt passed around a box of quinine as a preventive against
malaria； and again they lay back and looked at the stars。 The
most splendid sight in their sky now was Saturn。 At the
comparatively short distance this great planet was from them； it
cast a distinct shadow； its vast rings making it appear twice its
real size。 With the first glimmer of dawn； the fire…balls
descended to the surface of the water and disappeared within it；
their lights going out。 With a suddenness to which the explorers
were becoming accustomed； the sun burst upon them； rising as
perpendicularly as at the earth's equator； and more than twice as
fast； having first tinged the sky with the most brilliant hues。
The stream had left the forest and swamp； and was now flowing
through open country between high banks。 Pushing the raft
ashore； they stepped off on the sand； and； warming up the remains
of the mastodon's heart； ate a substantial breakfast。
While washing their knives in the stream preparatory to leaving
itfor they wished to return to the Callisto by completing the
circle they had begunthey noticed a huge flat jelly…fish in
shallow water。 It was so transparent that they could see the
sandy bottom through it。 As it seemed to be asleep； Bearwarden
stirred up the water around it and poked it with a stick。 The
jelly… fish first drew itself together till it touched the
surface of the water； being nearly round； then it slowly left the
stream and rose till it was wholly in the air； and；
notwithstanding the sunlight； it emitted a faint glow。
〃Ah！〃 exclaimed Bearwarden； 〃here we have one of our
Jack…o'…lanterns。 Let us see what it is going to do。〃
〃It is incomprehensible to me；〃 said Cortlandt； 〃how it maintains
itself； for it has neither wings nor visible means of support；
yet； as it was able to immerse itself in the stream； thereby
displacing a volume of liquid equivalent to its bulk； it must be
at least as heavy as water。〃
The jelly…fish remained poised in the air until directly above
them； when it began to descend。
〃Stand from under！〃 cried Bearwarden； stepping back。 〃I； for one；
should not care to be touched。〃
The great soft mass came directly over the spot on which they had
been standing； and stopped its descent about three feet from the
ground； parallel to which it was slowly carried by the wind。 A
few yards off； in the direction in which it was moving； lay a
long black snake asleep on the sand。 When directly over its
victim the jelly globule again sank till it touched the middle of
the reptile's back。 The serpent immediately coiled itself in a
knot； but was already dead。 The jellyfish did not swallow； but
completely surrounded its prey； and again rose in the air； with
the snake's black body clearly visible within it。
〃Our Will…o'…the…wisp is prettier by night than by day；〃 said
Bearwarden。 〃I suggest that we investigate this further。〃
〃How？〃 asked Cortlandt。
〃By destroying its life；〃 replied Bearwarden。 〃Give it one
barrel from your gun； doctor； and see if it can then defy
gravitation。〃
Accordingly Cortlandt took careful aim at the object； about
twenty…yards away； and fired。 The main portion of the jellyfish；
with the snake still in its embrace； sailed away； but many pounds
of jelly fell to the ground。 Most of this remained where it had
fallen； but a few of the larger pieces showed a faint luminosity
and rose again。
〃You cannot kill that which is simply a mass of protoplasm；〃 said
Cortlandt。 〃Doubtless each of those pieces will form a new
organism。 This proves that there are ramifications and
developments of life which we never dreamed of。〃
CHAPTER VII。
AN UNSEEN HUNTER。
They calculated that they had come ten or twelve miles from the
place at which they built the raft； while the damp salt breeze
blowing from the south showed them they were near the ocean。
Concluding that large bodies of water must be very much alike on
all planets； they decided to make for a range of hills due north
and a few miles off； and to complete the circuit of the square in
returning to the Callisto。 The soft wet sand was covered with
huge and curious tracks； doubtless made by creatures that had
come to the stream during the night to drink； and they noticed
with satisfaction as they set out that the fresher ones led off
in the direction in which they were going。 For practice； they
blew off the heads of the boa…constrictors as they hung from the
trees； and of the other huge snakes that moved along the ground；
with explosive bullets； in every thicket through which they
passed； knowing that the game； never having been shot at； would
not take fright at the noise。 Sometimes they came upon great
masses of snakes； intertwined and coiled like worms； in these
cases Cortlandt brought his gun into play； raking them with
duck…shot to his heart's content。 〃As the function of these
reptiles；〃 he explained； 〃is to form a soil on which higher life
may grow； we may as well help along their metamorphosis by
artificial means。〃 They were impressed by the tremendous
cannon…like reports of their firearms； which they perceived at
once resulted from the great density of the Jovian atmosphere。
And this was also a considerable aid to them in making muscular
exertion； for it had just the reverse effect of rarefied mountain
air； and they seldom had to expand their lungs fully in order to
breathe。
The ground continued to be marked with very large footprints。
Often the impressions were those of a biped like some huge bird；
except that occasionally the creature had put down one or both
forefeet； and a thick tail had evidently dragged nearly all the
time it walked erect。 Presently； coming to something they had
taken for a large flat rock； they were surprised to see it move。
It was about twelve feet wide by eighteen feet long； while its
shell seemed at least a foot thick； and it was of course the
largest turtle they had ever seen。
〃Twenty…four people could dine at a table of this size with
ease；〃 said Bearwarden； 〃while it would make soup for a regiment。
I wonder if it belongs to the snapping or diamond…backed
species。〃
At this juncture the monster again moved。
〃As it is heading in our direction；〃 resumed Bearwarden； 〃I vote
we strike for a free pass；〃 and； taking a run； he sprang with his
spiked boots upon the turtle's shell and clambered upon the flat
top； which was about six feet from the ground。 He was quickly
followed by Ayrault； who was not much ahead of Cortlandt； for；
notwithstanding his fifty years； the professor was very spry。
The tortoise was almost the exact counterpart of the Glyptodon
asper that formerly existed on earth； and shambled along at a
jerky gait； about half as fast again as they could walk； and
while it continued to go in their direction they were greatly
pleased。 They soon found that by dropping the butts of their
rifles sharply and simultaneously on either side； just back of
the head； they could direct their course； by making their steed
swerve away from the stamping。
〃It is strange；〃 said Ayrault； 〃that； with the
exception of the mastodon and this tortoise； we have seen
none of the monsters that seem to appear at the close of
Carboniferous periods； although the ground is covered
with their tracks。〃
〃Probably we did not reach the grounds at the right time of day；〃
replied Bearwarden。 〃The large game doubtless stays in the woods
and jungles till night。〃
〃I fancy；〃 said Cortlandt； 〃we shall find representatives of all
the species that once lived upon the earth。 In the case of the
singing flowers and the Jack…o'…lantern jelly…fish； we have； in
addition； seen developments the existence of which no scientist
has ever before even suspected。〃
Occasionally the tortoise stopped； whereupon they poked it from
behind with their knives。 It was a vic