THERE is no rock on the banks of the Hoogly, nor do we meet with any after entering on the main stream of the Ganges, until we approach the province of Bahar. The soil, in general, seems to consist of a mixture of argillaceous earth and sand, in such proportions as to make a soft attenuated compound, excellently adapted for the purposes of vegetation, and conducing, in a great degree, to that fertility for which the plains of Bengal are so celebrated. The only peculiarity in these ingredients of the soil is the great abundance of mica, which, mingled in minute grains, often gives a brilliant shining appearance to an extensive plain of sand, and is found to prevail, more or less, on the banks in the whole course of the river. Strata of sand, of various colours, are frequently lying over each other, which seem to have been formed in successive seasons; and above these, mixed soil or sand approaching to it, with a surface destitute of herbage, or bearing a coarse grass or reeds, in detached parcels. After leaving the low lands of Bengal, the Rajemahal chain of "hills presents itself, and diversifies the prospect and character of the country. Here, for the first time, we discover rock ; and from this point commences the series of specimens which is the subject of the