86 TRANSACTIONS OF THE [.TAN. 27, 



quantities of undigested horny wings, and other hard parts, of 

 insects. Seal-guano is also known on some coasts. All these 

 are geologically modern. 



In the Mesozoic era, abroad, we find the remarkable " copro- 

 lite beds," formed in a similar manner by the great marine rep- 

 tiles of the Jurassic time. These deposits have yielded thou- 

 sands of tons per year, in Suffolk and Cambridgeshire, and are 

 extensively and regularly worked like mines in many parts of 

 the Continent, from Spain toEussia. 



In our own country we have, besides the Laurentian apatite 

 before referred to, a series of phosphatic marls extending along 

 the seaboard region from New Jersey to Florida, and belonging 

 to the early and middle Tertiary. The most important are the 

 beds of the Ashley and Cooper river region in South Carolina, 

 which are different from any others previously known. They 

 were discovered in 1867, just after the war, and have been a 

 priceless boon to the State and the country, aiding greatly in 

 restoring the waste and desolation wrought by the war, both by 

 fertilizing the sandy lands of the whole Southern coast region, 

 and by furnishing a most important and profitable industry in 

 mining, preparing, and shipping the material. Their use is ex- 

 tending over the entire United States, and the demand seems 

 almost unlimited. 



The '' phosphate-rock '' had been observed and to some ex- 

 tent recognized in its character, years before. But much of the 

 land underneath which it lies is extremely barren, and perhaps 

 for this reason the material was not considered of any especial 

 value. I have myself analyzed soils that contain phosphoric 

 acid up to six per cent, but so lacking in other elements of 

 plant-food as to be wholly barren. Upon such lands it was that 

 Kavenel discovered the method of producing an abundant yield 

 by planting green crops and then "plowing undei\/' — thus fur- 

 nishing the organic material necessary to act on the insoluble 

 phosphates. 



These beds are a wonderful repository of fossil remains. They 

 consist largely of the so-called ''nodules" of phosphate- rock, 

 varying in size from a few millimetres to large masses; and inter- 

 mingled with these, but not included in them, are quantities of 

 bones and teeth of vertebrate animals, — sharks of great size, 

 manatee, horse, elephant, etc., — representing various periods 

 from the Eocene to the Pliocene Tertiary. The nodules contain 

 casts of fossil shells, but none of these vertebrate remains. The 

 question of the manner in which these beds originated is one of 

 great geological interest; but this is not the time for its dis- 

 cussion. 



During the past year (1889) it is reported that the amount 



