THE ROTIFERA OF THE SCOTTISH LOCHS. 187 



The jaws are exceptionally narrow, being only equalled by some of the pellet-makers, 

 the shape being in those cases quite different. In this the outline of the jaw is nearly 

 a perfect arc of a circle. 



Central setae were not observed on the discs. 



On such short acquaintance it is impossible to suggest the affinities within the genus. 

 Though no eggs were seen, the absence of foetus places it in the oviparous, non -pellet- 

 making section of Callidina, with C. plicata, etc. In appearance it has no close 

 relationship with the other animals in the section. 



Habits. — Free-swimming in company with Brachionus pala and Anursea valga. 

 When swimming, the rostrum and antenna are kept fully extended, the rostrum 

 projecting in front of the corona, concealing the upper lip. From the broad corona to 

 the toes, the general form is that of an elongate cone, though there is a narrowing at 

 the neck and expansion in the central segments. The foot is also kept fully extended, 

 even to the toes, and trails behind like a tail. 



Under the cover-slip it continually tried to swim, but, having too little room, was 

 often compelled to stop. It then wriggled on its side in an aimless fashion. The 

 little foot was drawn into the somewhat heavy trunk and shot out again, curling about 

 like a worm. It seemed to be unfamiliar with the use of the toes for creeping, and 

 some time passed before it made attempts in that direction. Even when it got on its 

 feet, the toes were never drawn into their sheath in the usual way, but kept extended 

 to their full length. 



The animal made its appearance in considerable numbers in a pond which dries up 

 in summer, within a week after the pond filled at the beginning of winter. The pond 

 is only a foot or two in depth, but when the collection was made it was calm and clear, 

 and the collection was taken without disturbing the bottom ; so there seems little 

 doubt that it is a true swimmer, if only in shallow waters, and its behaviour under the 

 confinement of the cover-slip confirms this. 



Habitat. — In a pond which fills each winter, and dries in summer, at Nerston, 

 East Kilbride. Fairly abundant on the day when it was detected, it has never been 

 again found, though the pond has been examined in the same manner at regular 

 intervals ever since. Fortunately, the original collection was sent to Mr Bryce, who 

 found some of the animals, and confirmed my diagnosis in some particulars, while 

 agreeing with me that it was distinct from any species previously seen. 



