l899 C. CALLAWAY— ON EARLIEST LIFE 8l 



made by a sea-worm ; and as they are sometimes found in 

 pairs, he gave them the specific name of didyina. He 

 presumably thought that the animal ascended by one of 

 the apertures and descended by the other. My own 

 experience is that these pairs are extremely rare, while 

 single pits occur in vast numbers. That the single and 

 double pits belong to different species may be considered 

 probable. I have also detected the traces of a fossil of 

 larger size, about one-eighth inch in diameter. It is in 

 the form of an annular depression surrounding a raised 

 ring, in the centre of which is a minute pit. This 

 structure would also seem to be connected with the 

 movements of worms on a sea-shore ; and in this opinion 

 I am confirmed by the high authority of Mr E. T. 

 Newton, F.R.S. On some of the slabs of shale there 

 appear linear elevations, which sometimes bifurcate Hke 

 the veins of a fern-leaf, and are aggregated in clusters so 

 as to suggest a Dictyonema, or a Polyzoan. I have one 

 specimen which looks as if it were an impression of a leaf 

 with parallel venation, but I incline to think that it is 

 merely the weathered outcrop of thin laminae of sediment. 

 The absence of any trace of carbonaceous or chitinous 

 matter in these rocks somewhat militates against the 

 belief that either, of the last two forms is really of organic 

 origin. My last fossils are in the form of oval depres- 

 sions, the largest of which are about half-an-inch in length, 

 and are well marked, with sharply defined edges. Others 

 are smaller and less distinct, and some are so minute as 

 to be scarcely visible. They can hardly be footprints, for 

 they do not occur in pairs ; but they certainly suggest 

 the action of living creatures. 



The evidence I have adduced clearly points to the 

 abundance of animal life in Longmyndian times. The 

 traces of organisms are often extremely obscure, but that 

 wormlike animals abounded on the shores of the seas is 



