304 
side of the body. On the expanding of the tentacle 
the blood instantly returns, and suffuses it; and thus 
the process goes on. The contraction and expansion 
occur at regular intervals, together occupying the 
space of twoseconds. It isin this way that the blood 
is purified and the circulation controlled. ‘The above 
observations were made with a seven-eighths inch 
objective, the subject being placed in a zoodphyte- 
trough. 
To ascertain how long the cilia upon the tentacles 
would continue their motion after separation from 
the worm, both lophophores of an adult were cut off 
above their own junction. At first the tentacles 
remained closed: but soon they expanded, the cilia 
displaying active motion; and presently the two sepa- 
rated lopophores began to move about in the zoo- 
phyte-trough. This motion was produced by the 
action of the tentacles, which bent in all directions, 
their tips touching the glass, and was not a result of 
ciliary currents. In a few minutes one lophophore 
had crawled in this man- 
ner quite across the 
trough, while the other 
remained floating in the 
water near its first posi- 
tion. Sometimes the 
motion was produced by 
ciliary currents, the ten- 
tacles remaining motion- 
less; but this was quite 
distinct from the crawling 
above noted. 
During this time the 
decapitated worm had 
sunk to the bottom, and, 
though twisting and turn- 
ing a good deal, did not 
attempt to protrude the 
SCIENCE. 
[Vou. IIL, No. 58. 
to a remarkable storm-cloud that lay along the east- 
ern horizon. As the sun grew low in the west, this 
cloud assumed most extraordinary proportions and 
colors; so much so, that it attracted almost universal 
attention. A strange, fan-like sheet of yellowish 
cloud, with broken but decided margin, rose above 
the centre of the storm like a great halo. It did not 
seem to stand in a vertical position, but projected 
above, toward the west, giving the effect of a huge 
funnel, viewed from below, on the exterior sur- 
face of which the descending sun cast shadows, 
and brought out a sort of radiate ribbed struc- 
ture. 
Beneath this was a great cluster of swelling cumu- 
lus ‘ thunder-heads,’ whose bases were hidden by the 
horizon. ‘Three of these, higher than the others, rose 
vertically froin the centre of the mass; their magnifi- 
cent fleece-like heads entering and apparently pene- 
trating the yellow halo. These, especially the middle 
and largest one, glowed brilliantly in the strong sun- 
mutilated support of the 
lophophores. Its body 
was so much contracted 
that the segments were 
not above one-third their 
usual size. 
At the end of five hours the worm was apparently 
dead; numbers of infusoria had collected to prey upon 
it; and the surface of its body presented a roughened 
appearance, as though covered with tubercles. The 
lophophores were still in motion. At the end of the 
eighth hour the lophophores had ceased to move, and 
were paler and more transparent; but the ciliary 
action, though feeble and uncertain, still continued. 
The body of the worm was then covered with a thick 
fungoid growth, consisting of transparent, rod-like 
filaments, three-sixteenths of an inch in length, 
some of the filaments having a beaded appearance. : 
All motion of the cilia upon the tentacles had now 
ceased, and these latter were also the prey of in- 
fusoria. 
The above experiment showed that the independ- 
ent motion of the cilia continued about twice as long 
as the mutilated worm gave evidence of vitality. 
Several individuals of Manayunkia were observed to 
be preyed upon while still alive by large monads, 
embedded in one or more segments, which were some- 
times excavated to a considerable degree. 
SARA GWENDOLEN FOULKE. 
Appearance of the cyclone cloud at Rochester, 
Minn., 1883. 
On Tuesday, Aug. 21, I left Minneapolis at three 
o’clock in the afternoon for Albert Lea, Io. 
Late in the afternoon my attention was attracted 
ieee 
light, and cast long blue shadows down the inclined 
under-surface of the halo. 
Encircling this brilliant mass were a number of 
enormous ‘ thunder-heads’ of a most murky and for- 
bidding appearance, that stood upright, like so many 
pillars of dense smoke. These upright clouds inclined 
a little to the east or south-east, indicating a move- 
ment in that direction. 
There was a remarkable stability about the whole 
mass of clouds, and at sunset the effect was grand in 
the extreme: The sky about was clear, with the ex- 
ception of isolated masses of cumulus-cloud. 
I made a small pencil-sketch of the cloud-forms, 
with notes of color, and, since my return to Washing- 
ton, have made a drawing i in color. 
I estimated that the cloud was from forty to fifty 
miles east of the railway, and, on studying the map 
carefully, became convinced that this was the cloud 
attending the great cyclone at Rochester. My atten- 
tion was not called 1o the cloud until after five 
o’clock, at which time it was directly east of me, at 
Wilton. As the course of the cyclone was a little to 
the north of east, the movement was directly from 
me when the sketch was made. 
The peculiar form of the halo, whether fan or fun- 
nel shaped, was doubtless, in a measure, the result of 
the movements of the storm-currents. 
W. H. HoLMEs. 
Geological survey, Washington. 
