182 



On Tubicolarta Najas. 



By James Fullagar, Hon. Assistant Secretary of the East Kent 



Natural History Society. 



(Read June 23rd, 1876.) 

 > Plates xvi, xvii, xviii. 



I have lately been making some observations upon a Rotifer, named 

 (in " Pritchard's Infusoria") Tubicolarta Rajas, and figured there as 

 inhabiting a transparent tube, into which at times the creature re- 

 treats. That which I have had under consideration certainly has a 

 transparent tube, as the animal can be distinctly seen through it, but 

 at the same time it is surrounded with brownish-coloured filaments 

 which appear to grow out of and around it, and attached to which 

 also are various diatoms and desmids, together with portions of 

 decayed vegetable matter. 



On one or two occasions Colonel Horsley exhibited specimens of 

 this rotifer, as a very pretty object, at the Canterbury meetings, 

 deeming it quite equal in beauty to Melicerta ringens. Though it 

 had no beautiful and curiously-formed case like Melicerta, nor had it 

 the pellet-making machine, yet it was a very interesting object under 

 the microscope. I obtained of Colonel Horsley a number of these 

 rotifers, found in some water he had taken some months back from 

 a dyke at Chartham, and which had been kept in a small aquarium. 

 I had them under my notice for a month, during which time I made 

 the following observations on their development from the ova. I 

 had often been puzzled when I had seen the eggs of these and like 

 creatures hanging loosely on the outside of their bodies, and have 

 wondered in what way they were developed ; I have now been able to 

 witness this, and some other peculiarities in their economy. At Fig. 1 

 is a sketch of the IVajas when it is placed so that the ciliated lobes 

 are equally expanded, and in a perfectly uniform position ; they then 

 present a very beautiful appearance, the cilia passing like an endless 

 band round the extended disks. By the action of these cilia, of 

 which there is a double row, a current of water is made to flow to- 

 wards the mouth in the direction indicated by the arrows, bringing 



