F. "NV. PHILLirS OBSERVATIONS ON ROTIFERS. 117 



matter. About a year ap;o one of the best ponds in the neiglibour- 

 hood was coinjiletely spoilt by the introduction of a dead cat. The 

 fastidious rotifers ivlused to associate witli it, and rapidly dis- 

 ajipeared, leaving the cat to the care of the Paramecia and 

 Monadina. 



In the early days of my microscopical studies I tried unsuccess- 

 fully to induce the growth of lotifors in infusions of decomposing 

 matter; but the only animalcules which rewarded my labours were 

 the Paramecia and a few sickly Vorticellidte. My want of success 

 was certainly not due to Avant of perseverance, for I filled a 

 quantity of gallipots and glasses with all sorts of vegetable matter; 

 but the odour which arose from them was adjudged by several 

 members of the household to be decidedly offensive, and I was 

 requested to transfer the scene of my labours to the outbuildings. 

 I thought it rather hard at the time that such obstacles should be 

 placed in the way of experimental science ; but subsequent 

 reflection has caused me to thiuk that perhaps the protest was not 

 entirely without foundation. 



Having thus given you some idea of what the Rotifera are like, 

 I will proceed to describe some of the species found in the neigh- 

 bourhood, giving the localities from which they have been obtained. 

 We will take them in the order of " thecated " and " fret; " 

 rotifers.* 



1. Foremost in the first group stands our celebrated friend 

 Ifelicerta ringens, OY " the building rotifer," which is remarkable 

 for its architectural habits. It inhabits an urceolus, or sheath, of 

 a conical form, composed of brownish-red pellets which the creature 

 secretes and deposits. I have never seen it build, but will give 

 you the substance of an elaborate paper written by Mr. Gosse 

 ('Trans. Micros. Soc' 1851). Beneath the ciliary wreath there is 

 seen a special rotating organ of a cup-like figure, which causes a 

 vortex and draws all particles into its cavity, where they are 

 whirled round and round and formed into pellets of a lenticular 

 figure, which the animalcule deposits by bending over towards the 

 margin of its sheath, to which they adhere by a viscid secretion, 

 which in time grows hard ; the first few rings are formed round the 

 middle of the body, and then pushed downwards towards the weed 

 which the creature adheres to ; each pellet takes about three 

 minutes and a half to make and deposit. Mr. Gilbertson tells me 

 that this operation extended to five in a specimen he observed. 

 The young Melicerta, after it escapes from the egg, swims freely 

 about for a time ; but after having sown its wild oats, it comes to 

 the conclusion that "there's no place like home," and forthwith 

 attaches itself to a weed, builds a tube, and then, like a sober 

 matron, spends the remainder of its days in tranquillity. The male 

 never builds a tube, but spends the whole of his brief existence in 

 making morning calls at the different tubes in his vicinity. 1 have 



* The numbers prefixed to the following paragraphs refer to the figures on 

 Plate II, aU of which are highly magnified. 



