190 



Note on a Mounted Slide of Trochosph^ea Solstitialis, 

 A Spherical Rotifer, exhibited at the Club's Meeting 

 ON February ITtii, 1899. 



By C. F. PtOUSSELET, Curator Pv.M.S. 



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The above diagrammatic sketch will give an idea of this remark- 

 able rotifer, which has not yet been found in Europe. This is the 

 lirst time that a mounted slide of it is exhibited, and that it is 

 seen at all in the flesh in England. 



In October 1859 Professor Semper discovered in some ditches 

 intersecting rice fields in the Philippine Islands a spherical 

 rotifer, which he named TrocJwsphcera cequatorialis. In this 

 animal the ciliary wreath runs round the equator, dividing it 

 into two hemispheres exactly alike. A translation of Professor 

 Semper's paper on his discovery was published in the " Monthly 

 Microscopical Journal" of 1875, vol. xiv., pp. 237—245. 



