district, Tenasserim (_Annandale_); Rangoon (_Annandale_); Bhamo, Upper Burma (_J. Coggin Brown_): CEYLON, Peradeniya (_E. E. Green_); outlet of the Maha Rambaikulam between Vavuniya and Mamadu, Northern Province (_Willey_); Horowapotanana, between Trincomalee and Anuradihapura, North-Central Province (_Willey_). BIOLOGY.--_S. carteri_ usually grows in ponds and lakes; I have never seen it in running water. Mr. Mackenzie found it on the walls of old indigo wells in Tirhut. The exact form of the sponge depends to some extent on the forces acting on it during life. At Igatpuri, for instance, I found that specimens attached to the stems of shrubs growing in the lake and constantly swayed by the wind had their surface irregularly reticulated with high undulating ridges, while those growing on stones at the bottom of a neighbouring pond were smooth and rounded. Sponges of this species do not shun the light. In Calcutta _S. carteri_ flourishes during the cold weather (November to March). By the end of March many specimens that have attached themselves to delicate stems such as those of the leaves of _Limnanthemum_, or to the roots of _Pistia stratiotes_, have grown too heavy for their support and have sunk down into the mud at the bottom of the ponds, in which they are quickly smothered. Others fixed to the end of branches overhanging the water or to bricks at the edge have completely dried up. A large proportion, however, still remain under water; but even these begin to show signs of decay at this period. Their cells migrate to the extremities of the sponge, leaving a mass of gemmules in the centre, and finally perish. Few sponges exist in an active condition throughout the hot weather. The majority of those that do so exhibit a curious phenomenon. Their surface becomes smoothly rounded and they have a slightly pinkish colour; the majority of the cells of their parenchyma, if viewed under a high power of the microscope, can be seen to be gorged with very minute drops of liquid. This liquid is colourless in its natural condition, but if the sponge is plunged into alcohol the liquid turns of a dark brown colour which stains both the alcohol and the sponge almost instantaneously. Probably the liquid represents some kind of reserve food-material. Even in the hot weather a few living sponges of the species may be found that have not this peculiarity, but, in some ponds at any rate, the majority that survive assume the peculiar summer form, which I have also found at Lucknow.