It has been thought proper to remove to this place certain notes relating to controverted points, in order that the perusal of the text may not be disturbed with petty and, as I believe, temporary cavils. For more abundant answers to objections of every kind, general reference is made to Explanations; a Sequel to Vestiges, &c.

NOTE A, p. 6.

The six-feet reflector, erected by the Earl of Rosse, near Cork, and first brought into operation in the latter part of 1844, resolved a great number of the nebulæ which had resisted other instruments of inferior power. Upon this, it has been rashly assumed, in some quarters, that all the celestial objects, usually called nebulæ, were proved to be clusters of stars, rendered cloudlike only by the vast distance at which they were placed. The truth appears to be, that the nebulæ now resolved were of that class which were always considered as liable to be ascertained as astral systems; while another class of objects, described in pp. 7 and 8 of the text, remained unaffected by these observations. See Explanations, pp. 8—13.

While the cartilaginous fishes which now exist reach lower down in the scale of organization than the osseous, and while their imperfect vertebral structure, heterocercal tails, and other peculiarities, indicate a general inferiority, some of them present characters in the nervous and reproductive systems, which the osseous fishes do not possess.