1897-98-] Microscopic Life. 305 



ferry Road, a water-trough and a small pond at House o' Hill 

 Farm, our own little Marchfield pond, Ravelston Quarry, and 

 the Marl Pit. We have also once or twice collected gatherings 

 from the Canal, the Elf Loch on the Braid Hills, and the pond 

 in the Botanic Garden, and these places are all very full of 

 interesting objects. We can always count on finding some 

 objects in special places of their own, as for instance Euglenas 

 on a spot in the Queensferry Road close by Blinkbonny Farm 

 after rain, and Chsetophora endivrefolia in Ravelston Quarry. 



When collecting from ponds, we use a small muslin net 

 fixed on a wire hoop at the end of a long stick, which can be 

 unscrewed to half its length if desired. We scrape the surface 

 of the mud gently with the hoop, and then empty the contents 

 of the net into a wide-necked glass jar filled with water. It 

 saves trouble to have a lid or cork for the jar, and to carry it 

 by a looped string. 



Among our earliest friends were the Rotifers : it is very 

 interesting to watch one feeding busily among algae, attached 

 by a strong forked tail to some support, while the wheel or 

 circle of cilia at its head is in rapid motion, setting up currents 

 in the surrounding water, and so drawing food-particles into 

 the creature's mouth. When the rotifer wishes, it can detach 

 itself and swim about freely. We used to bottle a good many 

 of our gatherings and open the bottles again after some time, 

 and we usually found that the rotifers were longer-lived under 

 these unnatural conditions than most of the other animal 

 organisms. We used often to open our old bottles, but have 

 given up doing so, as nearly all the organisms, whether animal 

 or vegetable, soon die in a corked bottle, and then the contents 

 smell very bad. 



From time to time we have found a great number of 

 Vorticellas of different kinds. They are graceful little bell- 

 shaped things, generally anchored by a long flexible stem, 

 which at any alarm contracts suddenly into a short spiral, and 

 then stretches more slowly out to its full extent, when the 

 cilia at once begin their busy movements. We have seen as 

 many as forty or fifty vorticellas at once in the field of view. 



The Infusoria (to which the vorticellas belong) are an 

 interesting class of creatures, and many of them are very 

 common, though it is rather difficult to identify them on 



