198 MK JAMES MURRAY ON 



another (fig. 18). These tail-like processes suggest a resemblance to those of the 

 swallow-tail butterfly. They are sometimes considerably longer than the foot. I have 

 seen no evidence that they are movable at will, but they certainly yield readily at 

 the base and assume many different positions. The position in which they are crossed 

 does not seem one likely to be produced automatically by the movements of the skin 

 to which they are attached. 



Habitat. — Among ground moss. Frequent, especially on mountain-tops. Fort- 

 Augustus ; Ben Lawers (cairn on summit) ; North Uist ; summit of Ward Hill in 

 Orkney, and of Ronas Hill in Shetland. 



Rotifer qvadrioculatus, Murray. Moorland, Fort-Augustus. 



Arthroglena lutkeni, Berg. Moorland, Pomona, Orkney. 



Stephanops microdactylus, Murray. Blantyre Moor ; Ballagioch Hill, near Glasgow. 



Cathy pna ungulata, Gosse. Mainland of Shetland. 



Brachionus bakeri, Ehr. Summit of Ronas Hill, Shetland. 



Rotifers found in the Sea. 



Though the Rotifers are pre-eminently a fresh-water group of animals, a considerable 

 number of marine species are now known. Besides those which are exclusively marine, 

 many species live indifferently in fresh or salt water. Seaweed was gathered on the 

 west coast of Scotland, kept tightly packed in a tin box for a week, then washed in 

 fresh water. A great many living Rotifers were then found which seemed active and 

 healthy in the fresh water. 



The Lake Survey did not make a special study of the marine species, but occasionally, 

 when opportunity offered, the nets were used in the sea, or seaweed was washed. 



Synchseta is a specially marine genus, or at least has a number of exclusively 

 marine species. In the harbour at Mallaig we found one species extremely abundant, 

 and in . the brackish loch of Stenness there were several species ; but we could not 

 venture to name these without submitting them to a specialist. We have found only 

 one Rotifer in the sea which has never occurred in fresh water. 



Rattulus dubius (Lauterborn) (5). In Morar Bay, West Inverness. Got by 

 washing seaweeds. 



Furcularia reinhardti, Ehr. This common lake species was also frequent in the sea 

 at Morar. The salt-water form was larger than the other, but I could see no other 

 difference. 



Philodina. Two species occurred in the washings of seaweed from Lochinver, West 

 Sutherland. They could not be identified. (P. Jlaviceps, Bryce, was got by Mr Wm. 

 Evans in the sea near Edinburgh.) 



Colurus, sp. In the washings of seaweed, one of the species occurring most 

 regularly is a large Colurus, which I will not attempt to name, in the present chaotic 

 state of the genus. 



Pterodina, sp. Lochinver. 



