18 JAMES MURRAY 



preserves them, secure against all other dangers, except only the advent ot 

 explorers. Their numbers prove how completely they are adapted to the local 

 conditions. I have never anywhere seen Bdelloid rotifers so plentiful as are the two 

 dominant species at Cape Royds (Philodina gregaria and Adineta grandis). 



Among the higher Invertebrata the Rotifers are easily first in numbers, both of 

 individuals and species. The Water-Bears are of only a few kinds, but one of them 

 (Macrobiotus arcticus) is extremely abundant. There are Nematode Worms of two 

 or more kinds, Mites of several kinds, and two Crustacea belonging to the 

 Entomostraca. The Ciliate Infusoria are very numerous, there are a good many 

 Flagellata, but only two Rhizopods were observed. 



The vegetation consists solely of Algae, Blue-green and Green, in filaments, 

 colonies, and single cells. The Diatoms are few and very small, and the Desmids 

 very rare, only two filamentous kinds being seen. 



In this paper a preliminary account will be given of the microscopic life, illustrated 

 with photographs from life taken on the spot, and with drawings. Some of the 

 groups, as the Rotifera and Tardigrada, will be worked up and reported upon in 

 separate papers. Other groups, especially the Infusoria, cannot be worked up in a 

 scientific manner. Such animals must be studied by a specialist on the spot. Most 

 of them cannot be preserved in recognisable condition, or to thus preserve them 

 requires special training and experience. Even were these objections inoperative 

 there is not time on such an expedition, with a limited scientific staff, to overtake 

 work of this kind. It is best that the specialist should give as much as possible of 

 his available time to the line of work which he is best qualified to deal with, and 

 outside of that do what he can. 



Such information as we were able to collect upon the Antarctic Infusoria, &c., in 

 the form of notes and sketches, will be here presented, without supposing that it can 

 be of much value to scientific students of these groups. A specialist looking at the 

 sketches might make a guess at the genera of some of the animals. Lack of know- 

 ledge prevented observations being made on various organs (mouth, nucleus, &c.) 

 which are important in determining species. 



Photographing the Microscopic Organisms. The first microphotographs were 

 made by Mawson, who had some previous experience. Mawson, however, could not 

 spare much time for this work, since he had all the physical observations to attend 

 to, as well as the preparations for a long sledge journey. After a few lessons from 

 Mawson the biologist was able to continue the work when Mawson had left on his 

 journey. 



It was not easy to find an opportunity for microphotography in our crowded 

 hut. During the day the tramping of feet caused too much vibration. We had 

 to wait for the hours of the night-watch before anything could be done, and 

 Mawson gave an entire night-watch to experimenting with different exposures and 

 plates. 



