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NOTES AND EXHIBITS. 



Mr. R. T. Baker brought forward herbarium specimens of the 

 leaves and fruits and economic specimens of the timbers of the 

 two species of Eucalypts in illustration of his paper. 



Dr. Greig-Smith exhibited a specimen of the dry gum of 

 Rhizobium leguminosarum and a solution to show its gelatinous 

 nature. Stained preparations under the microscope showed the 

 coccoid nature of the composite bacterium. 



Mr. T. Griffith Taylor exhibited numerous slabs and thin 

 microscopic sections of limestone containing fossil corals. The 

 points connected with the structure of these were explained by 

 means of lantern slides. The fossils were collected during a 

 visit to South Australia last February. The Archeocyathince 

 occur in a limestone belt extending four hundred miles in a 

 northerly direction from Port Victor to Lake Eyre. The best 

 localities appear to be at Sellick's Hill (30 miles south of Adelaide) 

 and the Ajax Mine, Beltana, about 350 miles north, near Lake 

 Torrens. From each of these places some two hundred specimens 

 were obtained, many slabs being from six to fourteen inches 

 across. The Archeocyathinse reef is probably the largest deposit of 

 Cambrian fauna in the world. Huge outcrops occur along the 

 line of strike, as at Normanville, Ardrossan, Wilson, Parachilna,. 

 Beltana, &c. The fossils vary in size from a diameter of 5 or 6 

 inches to small (or young) forms hardly discernible to the naked eye. 

 They are marvellously preserved, and the Beltana specimens 

 have undergone silicification to a great extent. This enables one 

 to etch them with wonderful results, each pore of the perforate 

 walls standing out as a white structure on the brown limestone. 

 Investigations during the past eight months lead one to the 

 belief that they possibly represent a link connecting the 

 Ccelenterata and Porifera. The numerous specimens of etched 

 material and serial sections for the microscope throw much light 

 on their morphology. Of especial interest are the methods of 

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