442 Proceedings. 



how many gradations there are, if measurement be taken as the sole 

 criterion. 



Mr. Travers said that where the bones were found mature, Dr. Haast 

 seemed to have determined their species by their relative proportions. Sup- 

 posing it should be ascertained that the test was not a good one, Dr. Haast 

 must be absolved from all blame, seeing that he had followed Professor 

 Owen. 



Mr. Mantell had not considered it necessary to state that he merely 

 wished to remark that Dr. Haast showed great courage in endeavouring to 

 determine species upon no other data than (what he took the liberty of con- 

 sidering) the very unsatisfactory test adopted by Professor Owen. 



2. " On Indications of Changes in the Level of the Coast Line of the 

 Southern Part of the North Island, as deduced from the Occurrence of 

 drift Pumice," by J. C. Crawford, F.Gr.S. 



Abstract. 

 Mr. Crawford remai^ked that pumice, having a small specific gravity, 

 floats in water, and in the rivers flowing from the volcanic plateau in the 

 interior of this island it may be seen descending in great quantities and at all 

 hours towards the sea ; when there, it is of course liable to be washed up at 

 any point of the shore, and if there is no cause again to carry it away, it 

 necessarily remains stranded. 



Pumice is found on the flats in the Peninsula, near this city, at a height 

 of about eight or ten feet above the present high watermark. He had not 

 observed it on any of the coast terraces, consequently it is probable that the 

 land had attained within ten to twenty feet of its present level before the 

 volcanic chain sent pumice to the sea; and this will give an age to the 

 present coast line, or to one from ten to twenty feet lower (supposing a 

 steady rise of the land), enough to satisfy a very ardent lover of antiquity. 



He concluded by saying, " It may therefore be held that the probabilities 

 are against any great oscillation of the present sea level in this part of New 

 Zealand since the commencement of the vast period which must have elapsed 

 since the central volca^nic group of Tongariro and Ruapehu (and Mount 

 Egmont inclusive) began to send down pumice to the coast." 



Dr. Hector said that pumice was a mechanical variety of obsidian, the 

 most pei'fectly fused product of volcanic eruption, and did not indicate 

 any particular era in a volcanic eruption, or elevation of a chain of moun- 

 tains, as Mr. Crawford seemed to require for his theory. The whole of the 

 eastern shore of Lake Taupo had been formed by wind-blown pumice. 

 Along some of the rivers that had cut through the slate rocks on their way 

 to the sea at Hawke Bay, there were terraces with pumice clinging to the 

 sides of the valleys 400 feet above the water, showing clearly that the 



