122 PROCEEDINGS OF THE ACADEMY OF 



observed there at one time. And by virtue of these long setae the 

 animal's facility for procuring prey was greatly enhanced. 



These minute objects which served as food were by a spasmodic 

 effort of the bristles gradually brought within the arms, and from 

 there, with this continued spasmodic movement which has been 

 described by Mr. Cubitt, were brought within the vortex induced 

 by an arrangement of cilia around the mouth, which, unlike the 

 setae on the tentacles, were, while the animal was feeding, kept in 

 a whorl. 



The action of the setae on the lobes of the Stephanoceros is 

 spasmodic; it creates no vortex, and it is only by actual contact 

 with these setae that floating particles are whipped within the area 

 inclosed by the lobes, where, by the same whipping action, they 

 are twitched from point to point, irregularly downwards, until they 

 come within the range of a vortex, which is due not to any action 

 of the setae, but to a range of minute cilia in the funnel, distinct 

 from the foraging appliances. 



For two weeks the animal under observation fed voraciouslv. 

 The last few da^ys of this time granular layers were rapidly de- 

 posited on each side of the body just within the case, until the 

 upper part of the carapace was distended with this accumulation. 

 For twenty-four hours following this condition but little or no 

 food passed into the digestive cavity; any infusoria or other 

 foreign substance accidentally coming within the tentacles being 

 immediately expelled by a sudden constriction of these organs at 

 their base. 



It was evident from appearances that some change was about 

 to take place. The animal, at first very sensitive, withdrawing 

 into its cell on the slightest jar of the table on which the instru- 

 ment was placed, now but seldom contracted its retractile muscle 

 even though the zoophyte-trough, in which it was examined, was 

 quite violently tapped. 



On the sixteenth day of observation it was unavoidably left 

 for a few hours ; on returning to it the tentacles, with the 

 above-described accumulated dark mass, were found to have left 

 the original case and were attached to a portion of the plant 

 beneath the branch to which it (the original case) adhered. It 

 now presented somewhat the appearance of an animal figured 

 and described by Pritchard as a young Stephanoceros, a dark 

 globular mass with five spreading or divergent tentacles, and at 

 the distal extremity a very slight prolongation by which it was 

 attached to a plant-stem by an almost invisible thread, devoid 

 entirely of any cell or carapace. Not long, however, was it 

 destined to remain in this nude condition, for in twenty-four 

 hours appearances of a cell were visible, and within three days it 

 was domiciled in as beautiful a spiral case as the one it had left. 

 Its contractile muscle developing rapidly with the length of the 

 cell, in a few days it presented to the observer all the peculiarities 



