Hutchinson. — On Scinde Island. 213 



aid of a hand-net in from 2 ft. to 4 ft. of water. These young 

 mussels were about the size of a pea ; the other shells ranged 

 down to the size of a small pin's-head. 



If this rule in any way holds good for other lakes, one can 

 easily see that, apart from their larger size, the chance of the 

 mussels being carried away by duck, or even the long-legged 

 wading pukekos, would be infmitesimally small compared to 

 that of the other shells. Certain it is that newly formed 

 pools are soon stocked, in some way or other. The pool re- 

 ferred to as having been formed only some two years ago has 

 now some four species of shells inhabiting it. I watched with 

 great interest the development of its fauna and flora. At first 

 -a raw stretch of yellow water, ebbing round di*owned docks 

 and grasses; its earliest tenants, and that in a very few weeks' 

 time, were the larval forms of gnats and dragon-flies. In 

 about a year's time young shells of Amphipcplea ampulla ap- 

 peared ; then, later, Potamopyrgus antipodum; then the white 

 shells of Pisidium ; and, lastly, the flattened brown form of 

 Planorbis corinna. Hosts of Gypris, a minute bivalve Crusta- 

 cean, appeared after the first year. Besides these, the pool, 

 now brown and clear, supports a mixed assemblage of lowly 

 organized plants: the wool-like green algae soon appeared; 

 brown blobs of the same family roll about the bottom, with 

 shapeless masses of clear jelly, and delicate network sacs, 

 evidently low forms of animal life. And all these were carried 

 in, I imagine, on the feet of wandering cattle, or by the 

 pukekos as they stalked to and from the adjacent well-stocked 

 creek and drain. 



These fresh-water shells are one of our few native families 

 that benefit by the introduction of an alien. Since the rapid 

 spread of that rampant cross-bearer, the water-cress, pools 

 and drains once dry during summer now lie shrouded in pro- 

 tecting green, affording pleasant moist shelter, and probably 

 food also, to these and a host of water-loving insects. 



Art. XXIII. — Scinde Island, from a Naturalist's Point of 



View. 



By F. Hutchinson, Jun. 



[Read before the Hawke's Bay Philosophical Institute, 9th July, 1900.] 



This is most emphatically not a deep paper from a scientific 

 point of view, being just a rough sketch of a few of the most 

 interesting features of the natural history of this most in- 



