1852.] BECKLES ON ORNITHOIDICHNITES. 397 



therefore less prominently from the surface of the stone. The two 

 bodies were placed one in advance of the other ; they had a uniform 

 direction, with a slight lateral inclination, one to the right and the 

 other to the left. The distance between them — from the middle 

 "toe" of the one to the "heel" or central protuberance of the 

 other — was 3 ft. 4 in. 



Fig. 2 exhibits the relative position of four " trifids " that were 

 exposed on a block measuring 9 ft. 4 in. by 4 ft. Two of t m, a, h. 



Fig. 2. 



presenting the ordinary form of these curious bodies, were parallel 

 with each other, and had a uniform direction. The other two, c, d^ 

 pointed in a different direction to that of the other pair, and followed 

 each other in a right line at a distance of 3 ft. 10 in. (measured from 

 the extremity of the longest toe of the one to that of the other) . In 

 this last pair the heel-like central protuberance was wanting, a con- 

 dition suggesting the idea that the original imprint might have been 

 made by a bird (?) passing quickly over the ground. On another 

 block, lying at a short distance from the above, was found a similar 

 pair of heel-less Ornithoidichnites, one in advance of the other, and 

 so much resembling the last-mentioned pair, c, d, in every particular, 

 even in the distance between them, or length of the stride, that they 

 had every appearance of being the continuation of the same track. 



In every instance these trifid bodies occurred on that surface which 

 was the under-plane of stratification when the blocks formed part of 

 the cliff. 



The distance separating the "trifids" when occurring in serie 

 varies from rather more than 2 feet to 3 ft. 4 in. (measured from 

 the toe of one to the heel of another). In consequence of this 

 distance between the ichnites, none of the blocks that came under 

 the author's observation as exhibiting one or more specimens could, 

 from their limited extent, have contained more than the number 

 actually observed upon them. 



The author observes, that having also discovered one example at 

 White Rock and another at the Sluice which is about ten miles to 

 the west of St. Leonard's — the extreme point in this direction where 

 the organic remains of the Wealden are obtained, he has detected 

 these singular trifid bodies throughout the entire section of the 

 Wealden on the Sussex coast, an extent of nearly eighteen miles. 



VOL. VIII. — PART 



