OP SANTO DOMINGO. , 109 



Jiat the author considers all of the red soil of the Bermudas, the "five sti'ata of Ireland " 

 island in the Bahamas, equally with this cave-soil, to be a guano deposit. If these 

 " earths " are similar to the red earth of the Dominican coast limestones his theory 

 is certainly false. 



In Trinidad the "■ ]S[ewer Parian" rocks, the "]S[ariva Series," probably the 

 equivalent more or less of the formation under consideration, are said to be " com- 

 posed of stiff feii'uginous clays with occasional limestones, constituting an undulating, 

 almost even surface, and affording soils of a more or less red color."* In J amaica 

 the " white limestone " yields a soil identical with the Dominican, and the description 

 given by the colonial geologist would apply equally well to this island,f except that 

 the "honey-combed" character is not so marked here as the description would seem 

 to imply in Jamaica. In Santo Domingo there are large tracts where not a single 

 stone is visible through the soil, and again there are regions where the soil only fills a 

 few crevices among the projecting points and ridges of the underlying limestone. 



The underlying rock and consequent soil produce a marked effect on the vegeta- 

 tion. J This is further modified by the access or deficiency of moisture in the air, so 

 as to produce a difference between the rainy and the nearly rainless ends of the Island. 

 But where the amount of moisture is the same on the plains of Seybo, for instance, 

 the limestone of the coast carries dense forests of tall trees with tangled undergrowtha 

 of bushes and vines, while the sands and gravels neai'er the hills are clothed only 

 with grass. 



There can be but little doubt as to the geological age of the coast formation. It 

 lies unconformably on the Miocene and consequentl}^ must be either Pliocene or later. 

 Its fossils are in a misei'able state of preservation, but a single locality yielding 

 moUusca in a recognizable state. In some localities internal casts are not rare, bat 

 while a few can be detected like the Lucinas by their well known form, oi- like the 

 giant St7'omhus by their size, the majority are entirely unrecognizable. Their only 

 vahie is to prove that many species existed, all identifiable traces of which are now 

 lost. 



* Trinidad Report, p. 74. 



■\ Jamaica Report, i>. 22. " Tlie white limestone formation seems to originate two descriiitions of alluvia — one 

 white, resembling a chalky marl ; the other red, free from carbonate of lime, the color being due to oxide of iron 

 combined with the ar.allaceous residue of the pre-existing limestone. This formation seems particularly susceptible 

 of disintegration aud removal, which is due to the solvent action of the rain-water under the high temperature of 

 this climate, and being probably also charged with free carbonic acid. The surface of the rock is thus worn into 

 holes which become larger with each successive shower, resulting in the well-known ' honey-combed ' appearance 

 which renders the rock so difficult to traverse." " The red variety of soil is so distinctive as to have originated the 

 appellation for the surface in several localities, as the 'Red Hills ' in St. Andrew's, &c." 



i See a note by myself, Amer. Jour, of Science, 1871, p. 137. 

 A. V. S. VOL. XV. 2b. 



