JOUKNAL 



OF THE 



ROYAL MICROSCOPICAL SOCIETY. 



FEBEUAEY 1881. 



TEANSACTIONS OF THE SOCIETY. 



I. — On CEcistes Janus and Floseularia trifolium, two new species 

 of Botifers. By C. T. Hudson, M.A., LL.D., F.R.M.S. 



(Bead 8th December, 1880.) 

 Plates I. and II. 



CEcistes Janus. 



The new tute-making rotifer, CEcistes Janus, was discovered by 

 Mr. J. Hood, of Dundee, in Loch Lundie, in September of this 

 year (1880). It appears to prefer deep water as its habitat, and 

 is found in the greatest number and best condition, Mr. Hood tells 

 me, at a depth varying from 6 to 10 feet. At first sight it was 

 naturally supposed to be a specimen of CE. pilula, which, so far as 

 its tube is concerned, it very closely resembles ; but the unfolding of 

 its trochal disk at once showed Mr. Hood that he had secured a prize. 

 CE. Janus is a most striking addition to the Melicertidse, for it 



EXPLANATION OF PLATES I. and II. 



CEcistes Janus. 

 Fig. 1. — Female in tube, antoral view, expanded. 



2. „ out of tube, nearly oral view, expanded. 



3. „ „ side view, expanded. 



4. „ „ „ closed. 

 5. — Trochal disk ; showing its thickenings. 

 6. — Extremity of chin. 

 7. — An antenna. 



Floseularia trifolium. 



Fig. 1. — Three females, from different points of view. 

 „ 2. — Side view of the body. 

 „ 3. — Back view of trochal disk ; showing the two rows of setfe down one 



side of a lobe. 

 In all the figures : — a, horseshoe row of small cilia ; 6, longitudinal muscles ; 

 c, antenna ; d, crop ; e, tube from mouth into crop ; /, mastax : g, ovary ; h, 

 stomach ; k, its lower division ; I, vent ; m, transverse muscle ; n, gastric gland ; 

 o, ganglion ; p, thickening of trochal disk ; r, cm-yed bristles ; s, knob-covering 

 gland ; t, ciliated chin. 



Ser. 2.— Vol. I. B 



