Irving: Lucernaria at Scarborough. 249 
fresh sea-water only, without any kind of weed or any apparent 
source of colouring matter, the pigmentation lines and spots 
were observed to darken in tint, grow in size, and invade all 
the tentacles. Detached from its natural anchorage, the little 
creature was for several days very restless, but there was no 
attempt to change its place by pulsation or otherwise. The 
somewhat flattened bell, lying on the bottom of the glass, if 
uninterfered with, displayed movements of body, of stalk, and 
of tentacles. The stalk was often considerably elongated and 
smooth in outline. It appeared to be in search of a suitable 
lodging place, curling itself first to one side, then to the other, 
now downwards, then upwards, revealing its anemone-like 
base or disc and aperture. When the stalk was touched with 
a pencil it immediately contracted to a third, or even a quarter 
of its length, withdrawing its disc and wrinkling itself into 
transverse folds and undulating margins, clearly indicating a 
sensitive and highly muscular organization. The bell-shaped 
body exhibited definite muscular movements consisting of 
expansion or contraction of one or more segments, the power 
to depress, to raise, or to turn the bell bodily over on to its 
tentacles. Capitate tentacles, few in number in this young 
specimen compared with an adult, were in groups of four, 
marking the summit of each of the eight cleft digitate processes 
which arise from the margin of the bell (Fig. 4). Each tentacle, 
however, had an absolutely independent range of movement 
apart from its fellows, or it could unite with those cf the entire 
tuft in concerted action. At the end of a week, failing in its 
quest for a stem of Halidrys, the young lucernarian actually 
attached its disc to the glass and there remained firmly adherent 
till it died. 
Lucernarians are classed amongst Jelly-fishes as Stauro- 
medus@, and while there are distinct points of resemblance to 
Meduse@, the general endowment of the race seems more in 
consonance with actinozoa. The pulsatile swimming so charac- 
teristic of Medus@ is non-evident, nor does the life-history 
reveal metamorphosis. On the other hand they possess a 
peculiarly sensitive aboral disc which in the case of Lucernaria 
campanulata always finds out Halidrys siliquosa, and apparently 
no other seaweed, for mooring purposes. Once attached to 
this, the muscular pedicle serves not merely as a suspender, 
but also as a complex lever for directing the body. Individuals 
are usually found on the floating weed, either on, or very near, 
the surface of the water where crustaceans and other small 
organisms abound. They are very voracious, even in captivity, 
and greedily seize with one or more tufts of tentacles anything 
coming in contact with them. A human finger, or the point 
of an ivory paper-knife, is caught with sufficient energy to 
permit an experimenter to drag the lucernarian about for a 
1913 July 1. 
