FLOSCULARIA HOODII. 293 



upwards and downwards by the contractions of the muscles and 

 by the various motions of the body ; the transverse muscles of the 

 trunk force the fluid into definite channels, rendering the lobes 

 tight and stiff, like the ribs of an umbrella. 



Doubtless the function of the finger-shaped processes on the 

 back of the dorsal lobe is to excrete a portion of the inter-mem- 

 branal fluid, which is then utilised in the construction of the fluffy, 

 gelatinous tube; and although no other species is known to possess 

 similar appendages, it cannot be said that the excretion of this 

 fluid is confined exclusively to F. Hoodii^ for there will be observed 

 on the back of the dorsal lobes of F. irilobata and F. ambigua a 

 single knob, and on the back and near the top of the dorsal lobe 

 of F. cucullata will be seen two slight prominences, which are 

 probably used for a similar purpose. The granules in the mucous 

 matter discharged have a very active swarming motion while they 

 cling round the free ends of the finger-like processes. This 

 swarming motion is not observed in the mucous fluid within the 

 two membranes of the skin in either of the lobes or the trunk. It 

 is only when the mucous matter is set free that the swarming, or 

 Brownian, motion of the granules is observable. 



Sometimes when the animal is fully protruded from its fluffy 

 tube, only one of the processes is seen to be fully distended ; the 

 other will be observed lying flat on the dorsal lobe ; then, in a 

 short time, it also will be slowly raised and distended. 



The corona is large and globular, and when fully expanded 

 shows a large, mouth-like funnel of three lobes, two small ones 

 being on the ventral, and one, much the largest, on the dorsal 

 side. The rims of the three lobes are clothed with a double 

 fringe of setae. The setae of the outer row are long and are 

 directed outwards. Those of the inner row are much shorter and 

 point inwards. The gap of the mouth-funnel alters frequently. 

 The food of these creatures consists of living animalcules of 

 various dimensions, one or more of which may be seen swimming 

 at the same time within its large circular cavity. To prevent the 

 escape of its victims, when the animalcules are of large size and 

 swift swimmers, the floscule closes the gap by means of the many 

 muscular threads on the corona, so as to reduce the aperture in 

 various degrees, at times even reducing it to a mere slit. 



