70 Proceedings. 



One very interesting photograph was that of tlie rifleman, the smallest of our native 

 birds. So small is it that Mr. Stead had discovered one making a nest in a 2 in. auger- 

 hole in a gate-post. The picture showed the female bird just entering the nest, in a 

 hole in the trunk of a large tree. 



Several pictures of blue or mountain ducks were showt\, the lecturer stating that 

 were they not so tame they would probably be more numerous. 



The female sparrow-hawk, he said, displayed extraordinary ferocity in the protection 

 of her young. If any one approached within a hundred yards of her nest she would swoo]i 

 do\\^l at the intruder from a great height. If any one were watching her, she would 

 approach within a foot and mount u]iwards again ; if any one were not watching, how- 

 ever, she would strike at his head with her claws as she .jjassed. The common harrier 

 was much more of a coward, and if disturbed on its nest would utter a protesting squawk 

 and fly away. Mr. Stead showed by specimens which he prodiiced that the female 

 sparrow-hawk was much larger than the male, as was the case with all falcons. In 

 New Zealand there were supposed to be two distinct varieties, and he said he was endea- 

 vouring to prove that the larger bird was the female and the smaller the male of the 

 same variety. His largest specimen coincided with the largest dimension given by 

 Buller for the female bird, and his smallest specimen coincided with the smallest dimen- 

 sions given for the male. He had found two birds of those descriptions mating, and 

 that, to his mind, disposed of the theory that there were two different varieties in New 

 Zealand. ||| 



The spotted shag fed entirely at sea, and the speaker entered a protest against 

 the organization of shooting parties which visited the Heads and shot hundreds of old 

 birds, leaving the little ones in the nests to starve. The big black shag built its nest 

 overhanging the water, so that on the slightest alarm the yovmg ones could drop over 

 the side and dive orrt of harm's way. The adult birds used the same nests year after 

 year, so that in the course of time they became quite prodigious structures. A remark- 

 able series of pictures was shown illustrating the manner in which the young shags 

 cking to branches by their feet, wings, or chins. 



The albatros Mi\ Stead described as a perfect aeroplane. Once started upon its 

 flight, and provided it made no mistake, it shoidd be able to continue its sailing without 

 once flapping its wings, either against the wind or with it. The remarkable mode of this 

 particular bird's flight was minutely d&scribed. It often happened, however, that, 

 owing to the whirls, vortices, and eddy-currents close to the water being so intricate, 

 albatroses, even after years of flight, were baffled and thrown out of their reckoning, 

 and had to flap their wings to counteract the unexpected influences. An excellent 

 photograph of a wandering-albatros was shown, and this was described by the speaker 

 as the long section of a perfect racing-yacht. 



The lecture concluded with a series of pictures of native bush. Mr. Stead explained 

 by means of these the haunts and habits of various native birds — from pigeons, which 

 delighted in low berry-bearing scrub furnished with tall trees, to the grebe, which built 

 a floating nest upon the edge of a remote lake or lagoon, and anchored its home to a 

 strand of flax. 



A hearty vote of thanks was accorded the lecturer. In seconding the motion ^ 

 Dr. Cockayne congratulated Mr. Stead upon his extremely accurate accotnit of native 

 bird life and habits. He said it was one of the scandals of our beautiful country that 

 such beautiful birds as the shags (except where there were trout-streams) should be 

 permitted to be destroyed. At Stewart Island, where there were no trout, the beautiful 

 Stewart Island shag was being shot out by pot-hunters. M'e tried to attract tourists to 

 inspect the wonders of our country, and yet little or nothing was done to protect the 

 native -bird life. 



Paper. — " On a Supposed Relation between Atmospheric Carbon- 

 dioxide and tlie Development of Plant-surface," by S. Page. 



This paper is an attempt to explain the evolution of leaves as resulting from a 

 gradual decrease in atmospheric 002- 



Taking the percentage of COj in air as 0-04, and of carbon in the earth as 0-02, every 

 8 in. in depth of the earth's crust contains carbon ecpial to that in the air. The COo 

 locked up in Cambrian and later limestones and in fossil vegetable matter exceeds that 

 at present in the atmosphere more than twenty thousand times. 



Most of this carbon was probably thrown into the air during the earth's 

 high-temperature period, any carbides formed being oxidized by metallic oxides and 

 silicates ; and has been again progressively removed by peat and carbonate formation 

 largely since Cambrian times. 



I 



