1897-98.] Lhe Upper Elf Loch, Braids. 371 
circumstance was the occurrence in the gathering of certain 
Entomostraca studded with an Epistylis—a ciliate infusorian 
allied to Vorticella. Of this remarkable combination there 
were numerous examples. The crustacean most particularly 
favoured in this respect was Cyclops strenuus, one of the 
species possessing long seventeen-jointed antenne; and the 
infusorian clustered upon these antenne from end to end, 
besides clinging to each side of the copepod’s body, and even 
to the extremity of its long forked tail. Epistylis differs 
from Vorticella in being branched, with the calyces borne on 
short, non-contractile stalks; and it was a remarkable sight 
to witness a Cyclops with a hundred or more of these in- 
fusorians attached to it, while the young free-swimming 
“buds” of the Epistylis revolved round the crustacean. This 
case 1s not an uncommon one, the conditions requisite for its 
production being a shallow piece of water with a quantity of 
decayed or decaying vegetable matter covering the bottom. 
The infusorian thus readily joins itself to the crustacean, and 
neither seems to suffer from the strange “attachment.” The 
Epistylis so attached was E. anastatica ; but another species, 
E. leucoa, was found on a water-bug, as well as on the un- 
protected portion of the body of a caddis-worm. 
The only addition to the filamentous alge during the past 
year was Draparnaldia glomerata, which was rather scarce,— 
indeed, with the exception of two or three of the commoner 
species of Spirogyra and Oscillaria, the members of this group 
are conspicuously absent in the Elf Loch. It is otherwise, 
however, with the motile or unicellular algee, which are fairly 
abundant numerically, though not generically. Yet Volvox 
globator was not nearly so plentiful in 1897 as in the year 
previous ; while in the present year, so far as yet observed, it 
is still scarce. This interesting alga is rather mysterious in 
its appearances and disappearances, and it almost seems as if 
some phases in its life-history were not yet perfectly under- 
stood. Our knowledge of the whole group of the motile alge, 
indeed, is still in a very unsatisfactory condition. Saville 
Kent, in his ‘ Manual of the Infusoria,’ regards Pandorina, for 
example, as synonymous with Eudorina; while Uroglena, 
Syncrypta, and some others, are said by him to be probably 
stages of development of Volvox or Pandorina. Some progress 
