ANNUAL ADDRESS, MDCCCLXXIII. 39 



there is sea there may be found in some parts or other 

 of it a growing quantity of limestone. In our times it 

 is represented by the great coral reefs now forming in the 

 bed of the deep sea, and in the accumulation of beds 

 composed of marine shells. This accumulation of lime- 

 stone will compare with that of any of the previous 

 geologic epochs ; nay, it will most probably surpass them. 

 It seems as though the older the earth grows the more 

 favourable is it for the forming of limestone. In the 

 Indian and Pacific Oceans, vast coral reefs are being slowly 

 but surely raised. They have been traced for 6,000 miles 

 in the latter, and in depth to more than 2,000 feet. Mr. 

 Jukes estimates that many thousands of years must have 

 been required for these tiny coral builders to raise the 

 barrier reef of Australia. 



The recent dredging researches in the Atlantic have 

 proved the existence of a soft bed of mud or ooze, which 

 when dried resembles chalk. It extends over the whole 

 floor of the Atlantic, except in the neighbourhood of cold 

 currents. Dr. Carpenter states that at a depth of three 

 miles he brought up in the dredge Ij cwt. of this ooze. 

 Ninety-seven per cent, of it consists of microscopic rhizo- 

 pods, or foraminiferous shells, which are the same globi- 

 gerinas I spoke of as constituting the bulk of chalk, and 

 those who favour the development theory have seized on 

 this fact as proving a continuity of specific forms of life, 

 at least from the chalk period to this. This, however, 

 meets with a serious check interposed by Sir C. Lyell, 

 who asks them to produce, in a living form, the now ex- 

 tinct shells which characterized the chalk period. You 

 will find under one of the microscopes the globigerinae 

 brought up by the dredge in the Atlantic dredging expe- 

 dition from a depth of two miles. You will have a good 



