Vol. 2 was published in 1846; Vol. 1 in 1848. Digital facsimiles of both vols. from Biodiversity Heritage Library at this link. Siebold was the author of  Vol. 1, on invertebrates; he introduced the taxa Arthropoda and Rhizopoda, and defined the taxon Protozoa specifically for single-celled organisms. Vol. 1 was translated into English and edited with notes and additions by Waldo I. Burnet as Comparative anatomy (London: Trubner & Co.; Boston: Gould and Lincoln, 1854). Digital facsimile of the English translation from Google Books at this link.

Stannius initiated research on the physiology of the conduction system of the heart. He illustrated vagal inhibition of the heart beat and indicated the existence of the pacemaker of the heart. Stannius also showed that the apex of the heart ceases to beat rhythmically when separated physiologically by ligature or clamp from the rest of the heart, while the sinus remains unaffected. Partial translation in J. F. Fulton’s Selected readings in the history of physiology, 2nd. ed., 1966, pp. 59-60.