1892.] MICUOSCOPICAL JOURNAL. 217 



with difficulty only. The short three-jointed foot carries two 

 long blade-shaped toes ; one of the individuals seen had one seta 

 on the foot ; the other, however, had none. 



Recapitulating the specific characters : Lorica egg-shaped, dor- 

 sal plate arched, occipital edge broadly notched, posterior edge 

 with narrow notch. Ventral plate small and flat. Size small, 

 1-130 inch without the toes. Toes rather more than one-third the 

 size of the body. Habitat, Keston, England. 



Callidina magna-caixarata. 

 By F. a. parsons, F. R. M. S., 



LONDON. ENGLAND. 



Callidina magna-calcarata. — T have the pleasure of bringing 

 to notice two Rotifers which are new to me. The one to which 

 I will first refer is a Callidina, which I found on the excursion to 

 Wood street in October, 1891. It is not, strictly speaking, new, 

 for my friend, Mr. Western, to whom I forwarded some speci- 

 mens, tells me he found it about two years ago, and Mr. D. 

 Bryce also informs me that he has known it for some time. In 

 endeavoring to discover if this Rotifer had been previously de- 

 scribed I found mentioned in the ^' Supplement" of Hudson and 

 Gosse a Callidina to which Kellicott gives the name socialis ; his 

 description of it agrees in several points with this, but does not fit 

 it in all respects, so that, in the absence of drawings o^ socialise I 

 have come to the conclusion that Kellicott's Rotiter and (his are 

 different species. 



I found it attached in pretty considerable numbers to the under- 

 side of Aselliis. and Mr. Western has found it also on Gatn- 

 7narjis. The body has numerous segments and has a very stout 

 appearance when seated on the Asellus^ with rotary organs ex- 

 panded in the act of feeding ; its greatest diameter lies towards 

 the upper part of the body, where it enlarges rather suddenly. It 

 then gradually tapers towards the foot. When swimming it is 

 more elongated, and consequently less in diameter. The corona 

 is broad, measuring about 4;he same width as the largest part of 

 the bod}^ when the animal is swimming. The column is stout, 

 the tip furnished with what appears to be a ciliated cup with a 

 hood-like projection extending partly over it. The dorsal an- 

 tenna is small, surmounted by sette, which are retractile by the 

 invagination of the tip of the antenna. Number of toes normal. 

 When the animal is crawling on the cover-glass, the toes have a 

 lengthy and pointed appearance as they are withdrawn. The 

 contractile vesicle is small, and is situated in the foot immediately 

 below the intestine. 



We now come to the most conspicuous featiu-e in this Rotifer, 

 viz., the spurs, two in number. These are large and striking, of 

 gracefully curved outline, broad at the base, with heels at the 



