MICROSCOPIC LIFE AT CAPE ROYDS 21 



kinds were common, one of which is figured on Plate IV., Fig. 13. Another kind 

 had the skin minutely annulate. 



Injusoria. In dealing with the lowest and simplest forms of life, which are 

 easily carried about in the form of dust, there must always be some doubt as to 

 whether many of the species are native or introduced by the expedition making the 

 observations. 



When we arrived at Cape Eoyds the season was well advanced towards autumn, 

 and nearly all the lakes were already frozen. When we cut out blocks of ice 

 containing portions of the vegetation which so abounds in these lakes we found many 

 kinds of Infusoria, some of them of large size, dead and embedded in the ice. These 

 were undoubtedly native. Afterwards, when the lakes melted and living Infusoria 

 appeared in them, we were able to recognise many of them as of the same kinds which 

 we had previously found frozen into the ice. Some of them were encysted and 

 probably alive when found in the ice, but we never observed any of them leaving the 

 cysts while under observation. 



One of the puzzling organisms which we first observed consisted of clusters of 

 whitish elliptical bodies, in which no definite organs could be seen. They were 

 supposed to be some kind of eggs. Long afterwards they were accidentally dis- 

 covered to be Vorticellids. On treating with formalin an "infusion" in which a kind 

 of Vorticellid abounded, it was found that they contracted into the puzzling egg-like 

 bodies. 



There is little doubt that most, if not all, of the Infusoria and other organisms 

 hereafter figured were true natives of the lakes of Cape Royds. The number of kinds 

 seen was much greater than the number noted and figured. Very many were seen 

 at times when important observations were in progress, which allowed of no time 

 being given to side issues. The Flagellata, on account of the greater difficulty 

 attending their study, were generally passed over without note. 



Rhizopoda, The paucity of Rhizopods at Cape Royds was surprising, after it 

 became known that so many other kinds of microscopic life abounded in the lakes. 

 In the lakes only two testaceous species were observed : the well-known Difflugia vas, 

 and a very small kind which appears to be a Quadrula. Among the moss there was 

 another species, not identified. 



On one occasion, when the ice of a lake was melted, we found numbers of an 

 amorphous granular organism, each with a round nucleus, which were probably 

 Amoebae, but being only seen dead nothing could be made of them. 



When our material is submitted to a specialist it is expected that he will find 

 other forms which we have overlooked.* 



Heliozoa, In Coast Lake in April 1908, there occurred an animal which appears 



* Dr. Penard has, in fact, detected about a dozen species, which will be reported upon in a subsequent 

 paper. 



