[47] “The doctrine of typical nuclei seems only a mode of evading the difficulty. Experience does not give us the types of theory; and, after all, what are these types? It must be admitted there are none in reality. How are we led to the theory of them? Simply by a process of abstraction from classified existences. Having grouped from natural similitudes certain natural forms into a class, we select attributes common to each member of the class, and call the assemblage of such attributes a type of the class. This process gives us an abstract idea; and we then transfer this idea to the Creator, and make Him start with that which our own imperfect generalization has derived.” (Address, &c., by +William R. Grove+, Esq., Q.C., M.A. 8vo, London, 1866: p. 31.) [48] See Dr. Bennett’s excellent notes on the living _Didunculus_, in the ‘Proceedings of the Zoological Society of London,’ 1864, p. 139. [49] To my friend Dr. Bennett I owe the first specimens of the _Nautilus pompilius_, impregnated uterus of the Kangaroo and Ornithorhynchus, the young Ornithorhynchus, and other rare subjects of early Memoirs. Natural History owes much to this accomplished and indefatigable Observer. [50] The scapular arch is rotated in advance of the ribs to show the character of the anterior dorsal vertebræ. [51] See also Gould, ‘Birds of Australia,’ part 22 (March, 1846). [52] I beg to return my acknowledgments to the Trustees of the Liverpool Museum for the opportunity of figuring two specimens, in this Plate, from the collection of Dodos’ bones in that Museum. Transcriber’s Notes: • Text enclosed by underscores is in italics (_italics_). • Text enclosed by pluses is in small caps (+small caps+). • Blank pages have been removed. • Obvious typographical errors have been silently corrected. • Page 33 refers to Plate XV, it does not exist, nor could I find an image with a “dotted outline” of a bone.