Mifieralogi/ and Geology. 



69 



between the parasite and the stock is such, " as can only be explained on 

 the supposition, that the germinating seed of the parasite excites a specific 

 action in the stock, the result of which is the formation of a structure, 

 either wholly or in part derived from the root, and adapted to the support 

 and protection of the undeveloped parasite ; analogous, therefore, to the 

 production of galls by the puncture of insects." On this supposition may 

 be explained, the connection between the flower Rafflesia and the root 

 from whence it springs. {Trans. Lin. Soc, vol. xiii. p. 227.) 



Art. IV. Mineralogy and Geology, 



Colour of the Red Sea. — The colour of the Red Sea has given rise to 

 various investigations. Dr. Ehrenberg, who accompanied Dr. Hemprich, 

 ascertained that it was caused by a species of Oscillatoria, one of those 

 small plants which are intermediate between animals and plants. {Jam. 

 Phil. Jour., Dec. 1827, p. 182.) 



Footmarks of Animals in Sandstone. — Numerous impressions of the foot- 

 steps of quadrupeds have been discovered on a bed of red sandstone, near 

 Lochmaben, in Dumfriesshire, between 60 and 70 ft. beneath the surface. 

 Professor Buckland, to whom specimens" of them have been sent, has given it 

 as his opinion, that they were produced by the feet of a tortoise or croco- 

 dile, at a time when the rock was in a soft state, and before the 60 or 70 ft. 

 of solid strata with which it is now covered had been superimposed. {Ibid.) 



Fossil Shell attached to Flint. — Dear Sir, I enclose a sketch of a fossil 

 shell attached to a flint {fig. 39.), which I found, some time ago, at Ditch- 

 ingham, in this 

 neighbourhood. I 

 can offer you no 

 theory, or other 

 information re- 

 specting it. 



About a year 

 and a half ago, as 

 some workmen 

 were digging in a 

 gravel pit at Wort- 

 well, within four 

 miles of this place, 

 they found the 

 fragment of an 

 elephant's tooth, 

 weighing upwards 

 of 3| lbs. It was 

 about 40 feet be- 

 low the surface. This and the flint are in the possession of J. B. Scott, 

 Esq. I am, dear Sir, &c. — Daniel Slock. Bungay, April 1. 1828. 



The specimen figured by our correspondent, is evidently the fossil bivalve 

 Inoc^ramus. No less than twelve species have been described by natural- 

 ists, of which three are peculiar to the upper chalk j four are common to the 

 chalk and the subjacent green sand ; one to the green sand and blue marl ; 

 one to the oak-tree clay ; one other species common to the oak-tree clay, 

 Falkstone marl, and green sand ; one to the alum strata ; and one to the 

 mountain limestone. The species here represented appears to be a small 

 variety of Inoc^ramus Cuvieri of Sowerby, tab. 441. {fig. 40.) This genus is 

 abundantly found in the diluvial gravel of the eastern counties, some frag- 



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