396 PROCEEDINGS OP THE GEOLOGICAL SOCIETY. [Juiie 16, 



The author then describes the occurrence of gold in the Lower 

 Silurian rocks. It is found disseminated, in small foliaceous particles 

 or in round grains, in the quartz-veins which traverse the greywacke 

 sandstone and shale in a direction generally at right angles to their 

 strike ; and also in the detritus of the same rock. A specimen 

 weighing 240 grains was lately found. The district furnishing the 

 gold lies to the north of the zone of black slate which runs from 

 Stobo through the summit- cutting of the Caledonian Railway and 

 Glenochar in the direction of Cairn Ryan. It is greatly disturbed, 

 not only by the quartz-veins, but by dykes of felspar and greenstone ; 

 and the dip is the reverse of that which usually prevails. Mr. Hark- 

 ness believes that the occurrence of gold is not connected with any 

 particular portion of the Silurian series, but rather with the presence 

 of the quartz- veins and the influence of the plutonic rocks. 



5. On the Ornithoidichnites of the Wealden. 

 By S. H. Beckles, Esq. 



[Communicated by Sir C. Lyell, V.P.G.S.] 



[Abstract.] 



Since the publication in January 1851 * of the notice of the pecu- 

 liar trifid bodies occurring in the Hastings rock, the author has 

 added several specimens to his collection, some of which appear to 

 afford additional evidence in favour of the opinion of their being 

 natural casts of the prints of birds' feet. 



To the west of St. Leonard' sf the specimens occur on small blocks 

 lying on the beach and subjected to tidal action. These as yet have 

 presented solitary ornithoidichnites only. To the east of Hastings, 

 however, the trifid bodies are found under more favourable circum- 

 stances. At a distance of between six and seven miles from St. Leo- 

 nard's immense blocks of stone, some of them several tons in weight, 

 lie for some distance along the beach in confused masses, immediately 

 at the base of the cliff and above high-Water-mark. On these blocks 

 the ornithoidichnites are frequently found, and sometimes in pairs 

 or groups. The following specimens have been selected as being 

 of most interest. 



Fig. 1 is the outline of one of Ym. 1. 



two of these bodies which were 

 found on the surface of a block 

 measuring 7 ft. 3 in. by 4 ft. They 

 differed from the usual form in 

 having a posterior elongation, 

 which was about two -thirds the 

 length of the "trifid," and less 

 than half its height, — projecting 



* Quart. Journ. Geol. Soc. vol. vii. p. 117. 



f One specimen was obtained also in digging the Railway tunnel between 

 St. Leonard's and Hastings. 



