H. W, KING ON POND LIFE FROM THE WEST INDIES. 148 



Rj these Rotifers having the capacity of retaining their 

 vitality after being dried up, the species is adapted for a very 

 wide distribution, for should the ponds in which they live be- 

 come dry, as frequently happens, the wind would waft these 

 dormant spheres of life, like dust, from one locality to another, 

 and when falling on suitable spots, and conditions being favour- 

 able, would become reanimated and originate fresh centres of 

 development. 



Another allied species was numerous in the water from Port 

 Limon, but differing from the one just considered by having an 

 orange-coloured body ; this, however, may be mainly due to the 

 different kind of food and the water in which it lives, as cater- 

 pillars and other life are frequently modified in colour by their 

 diet. Whether from a different habit or owing to their large 

 numbers, they appeared to be more associated in a colony, I 

 had as many as five under the microscope at a time, and the 

 tubes seemed to be more anastomosed together and crossing one 

 another in various directions, forming a small matted mass. 

 From the thicker, more opaque nature of their tubes it was not 

 so easy to observe their habits as in the case of the preceding 

 kind. This difference in their dwelling was probably due more 

 to the different materials used giving them an altered aspect 

 than from any variation of instinct action in their individual 

 construction. 



Both this variety and the former were very unaffected at 

 sudden sounds and shaking, a different characteristic to that of 

 most free swimming Rotifers, no doubt due to a sense of security 

 felt in their closed dwelling. 



A Rotifer (Fig. 6, PI. VIII.) living in and also utilizing earthy 

 matter for a protective purpose was at home in the water from 

 Colon. This animal usually imbed^ itself in the earthy matter 

 in the water aggregated either among weeds or at the bottom. 

 The lower portion of the body imbedded is curved, as it has 

 so small a foot that it would be useless in retaining it in 

 safety in so light and flocculent material were it not for this 

 modified shape of its body forming, as it does, a larger surface 

 for resistance. When disturbed it draws itself in below the 

 surface, and the opening through which it passes in and out 

 closes over it, so that it becomes buried until it feels the 

 threatened danger has gone, when it may be seen to slowly un- 



