Geological Society. 4 79 



out by Mr. J. Pringle. For tlie first 1200 feet the hole was 

 I)uiifht'd, and nothing is known of tlie strata traversed down to 

 that depth — beyond the fact that the boring started in the top of 

 the Middle Chalk and j)assed through scune Oxford Clay, and, behw 

 that, some oolitic limestones which presumably belong to the Great 

 Oolite Series. From 1200 feet the hole was drilled for 64 feet, and 

 cores were preserved. The cores consisted of alternations of lime- 

 stone and mudstone, with a rich and characteristic Upper Ludlow 

 fauna. Among the fossils was Orthoctras damtsi Kd-mer, 

 [■f Krause], which had not previously been obtained in this 

 country. 



The boring serves to fix part of the northern Iwundary of the 

 tract of Old ]{ed Sandstone which underlies London. It is 

 intended to publish a full account in the next issue of the 

 Summary of Progress of the Geological Survey. 



February 18th, 1016.— Dr. A. Smith Woodward, F.R.S., President, 

 in the Chair. 



The President, in his Anniversary Address, discussed the use 

 of fossil remains of the higher vertebrates in strati- 

 graphical geology. The study of fossil fishes, to which he had 

 referred in his Address of 1915, raised the question as to whether 

 animals of apparently the same family, genus, or species might not 

 originate more than once from separate series of ancestors. The 

 higher vertebrates, which inhabited the land, might most profitably 

 be examined to throw light on the subject ; for the land has always 

 been subdivided into well-defined areas, isolated by seas, mountains, 

 and deserts, so that animals in these several areas must often have 

 developed independently for long periods. Students of shells are 

 unanimous in recognizing what they term homoeomorphy, and trace 

 immature, mature, and senile stages in the course of eveiy race that 

 can be followed through successive geological formations. Verte- 

 brate skeletons, which have much more numerous and tangible 

 characters, and approach senility in more varied ways, should afford 

 a clearer view of general principles. 



Even among vertebrates the evidence that most concerns the 

 geologist is not always easily interpreted. For instance, the 

 Sparassodonta and horned tortoises of the Argentine Tertiary 

 are so closely similar to the existing Thylacines and the fossil 

 Miolania of Australia, that they are still sometimes quoted as 

 proving the former existence of an Antarctic Continent uniting 

 the South American and Australian regions. On the other hand, 

 they may be merely survivors of cosmopolitan races at the two 

 extremes of their former range, with certain inevitable (but not 

 altogether similar) marks of senility. In making comparisons, 

 indeed, it is no longer enough to distinguish the fundamental 

 and merely adaptive characters of animals; it is also essential 

 to note separately those characters which depend on the early, 



