The Rotifcra of South Africa. By Charles F. Rousselet. 395 



this rainless season, I carried my collecting stick everywhere with 

 'me, and the net, with bottle attached, in my pocket, so as to be 

 able to take advantage of every opportunity that might present 

 itself. 



From August 18 to September 17 the greater part of the time 

 was spent in the railway train, which formed our travelling hotel 

 and headquarters, only getting off and staying a few days at 

 Durban, Pietermaritzburg, Johannesburg, Bloemfontein, Kim- 

 berley, Bnlawayo and Victoria Falls, and a few hours at Salisbury, 

 Umtali and Beira, being everywhere received with the greatest 

 hospitality. I had taken with me a small folding binocular Micro- 

 scope, but examination of the living material was quite out of the 

 question, as there was absolutely no time or opportunity of doing 

 so, and therefore I preserved the collected material mostly in the 

 train in the following manner. After condensing the Kotifera as 

 much as possible with the net in the usual way, I filled a some- 

 what tall 3-ounce bottle and added a little 1\ p.c. formalin and a 

 very few drops of osmic acid ; this killed all the animals and sent 

 them to the bottom ; after allowing the bottle to stand for half-an- 

 hour, I carefully poured away the clear upper part of the water, 

 and then transferred the remainder with sediment into a smaller 

 bottle, adding again a little of the formalin. When the animals 

 and debris had again settled at the bottom, the subjacent water 

 poured away or removed with a pipette, I filled a small tube bottle 

 with the remainder, and after allowing this to settle once more for 

 half-an-hour I removed half of the clear water with a pipette and 

 filled up the tube bottle with 2\ p.c. formalin ; thus the contents 

 were finally preserved in about 1 p.c. formalin for examination at 

 home. 



As this rough method of preservation, the only one available 

 under the circumstances, has given fairly good results, I have 

 described it in detail ; of course all the Rotifers are fully con- 

 tracted, but all the forms could readily be identified, and the shape 

 of the loricated forms is well preserved. In the absence of osmic 

 acid, formalin alone, or even alcohol, might be used in the same 

 way. It would, however, be preferable, if time permitted, to 

 narcotise the Rotifers first with a few drops of 1 p.c. solution of 

 /3 Eucai'ne for a quarter of an hour before killing. 



The different localities where I was able to collect being situated 

 in widely separated areas, hundreds of miles apart, I will give a 

 separate list of the species found in each locality, which may be 

 useful to future collectors in the same districts. 



Capetown afforded but a poor opportunity of searching for 

 Rotifers ; the four days we stayed there were spent in attending 

 to the meetings and business of the British Association, and in 

 viewing this beautiful town and country around. Unfortunately, 

 I discovered too late, after I had climbed 3000 feet to the top of 



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