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these being curved and irregular in various ways, he compared 

 with the veins in the various recent pahia leaves, which are also 

 horizontal, and explained that these veins being composed of 

 annular vessels, under vertical pressure would form exactly such 

 fissures as are observed in the fossil. The only difficulty attend- 

 ing this explanation was, that some fossil specimens contained 

 these horizontal fissures of such large dimensions that some of 

 these foliar appendages must have been of much larger size than 

 any now existing ; still he thought he could produce other fossil 

 proof of the existence of this enormous foliage. 



He also pointed out on some specimens what he thought must 

 be large vertical sections of vegetable stems. 



In reply to a question from Prof. Rogers, Mr. Teschemacher 

 said, that under the microscope the coal strise lose their definite 

 outline, and no organic texture is made out. 



Prof. Rogers said, that in many specimens he could see no 

 trace of vegetable substance, and he thought the fissures might 

 have been caused by fracture. He thought that vegetable struc- 

 ture would manifest itself, if it existed, under the microscope. 

 He was inclined to question the accuracy of Mr. Teschemacher's 

 hypothesis as to the origin of the silicic acid in the fissures. He 

 thought that that, as well as the scales of silica found in anthra- 

 cite, might have been deposited by sublimation. He must, there- 

 fore, he said, renew his demurrer, formerly expressed, as to the 

 soundness of Mr. Teschemacher's theory. 



Mr. Teschemacher said in reply, that he had specimens which 

 had been ground and polished, which, under the microscope, 

 showed a structure precisely like that of palms. 



Dr. Burnett read a paper on the Embryology of Articu- 

 lata, as illustrating some obscure phenomena in the physi- 

 ology of generation. 



He explained in detail the successive development from the 

 ovum of the different parts in the animals of this order. In the 

 formation of the extremities of insects, a process takes place 

 similar to that of the first stages of development of the whole 

 body. As the whole body was at first a cylindrical blastemal 

 mass, subsequently marked by transverse grooves indicating its 



