(EXCLUSIVE OF ARTICLES IN SCIENTIFIC PERIODICALS, ETC.)
“De telis quibusdam Astaci fluviatilis.” Dissertatio inauguralis histologica. [48 pp. and 2 plates.] 1857.
“De rhizopodum finibus et ordinibus.” Diss. pro venia legendi impetranda. 1861.
“Die Radiolarien (Rhizopoda radiaria).” [Vol. i., 572 pp. fol.; vol. ii., 35 plates.] 1862.
“Beiträge zur Naturgeschichte der Hydromedusen. Die Familie der Rüsselquallen (Medusæ Geryonidæ).” [204 pp. and 6 plates.] 1865.
“Generelle Morphologie der Organismen.” [Vol. i, xxxii and 574 pp. and 2 plates; vol. ii., clx and 462 pp. and 8 plates.] 1866.
“Natürliche Schöpfungsgeschichte.” [568 pp. and 9 plates.] 1868. [10th edition, 1902.]
“Uber die Entstehung und den Stammbaum des Menschengeschlechts.” 1868.
“Zur Entwickelungsgeschichte der Siphonophoren.” Crowned by the Utrecht Society of Art and Science. [124 pp. 4to and 14 plates.] 1869.
“Uber Arbeitstheilung in Natur und Menschenleben.” 1869.