321 



SOME FURTHER NOTES ON COLLECTING AND 

 MOUNTING ROTIFERA. 



By C. F. Rousselet, F.R.M.S. 



{Read in Title October '2Zrd, 1917.) 



Since 1893 I have published various memoirs on my methods of 

 preserving and mounting Rotatoria, which from time to time 

 have been modified and improved upon. It is my belief that I 

 liave now succeeded in arriving at a fair degree of perfection for 

 fluid mounts and seeming a realty lasting method of mounting 

 such slides, and it is my object in the following pages to 

 recapitulate the steps which have led to this result, some of 

 which liave not been recorded before. The members of the 

 Q.M.C. need scarcely be told how Rotifera are caught and 

 examined ; I will therefore only briefly mention the methods I 

 have used for years for collecting them in large numbers and 

 with the least possible difficulty. The starting-points for these 

 methods I learned at my first attendance at the Q.M.C. excursion 

 meeting in May 1883, in the north of London, probably Hamp- 

 stead Heath, led by Mr. John Hardy. I collected from the very 

 first with the Q.M.C. collecting-stick and net, as sold by C. Baker. 

 The collecting-stick in the shape of a walking-stick with a tele- 

 scopic joint, so that its length may be nearly doubled when 

 required, was invented by Mr. Highley about 1868, as mentioned 

 by Lionel S. Beale, F.R.S., in the 4th edition of his book, Hoiv 

 to Work ivitJi the Microscope (p. 147), and figured on pi. 35, 

 fig. 224. The net is an old Q.M.C. institution and was probably 

 introduced by Mr. Thomas Curties, of C. Baker's firm. It was at 

 first made with the thin muslin known as soft mull, but later on 

 I introduced silk (bolting silk No. 15 or 16) made in Switzerland 



