Challenger Reports (Stalked Crinoids), vol. xi. pt. xxxii. 1884.
Stammesgeschichte der Pelmatozoen, pt. i. 1899.
"Die Echinodermenlarven der Plankton Expedition," Ergebn. Plankton Exp. Bd. ii. J, 1898.
"Über die Larvenzustande und die Metamorphose der Ophiuren und Seeigel," Abh. K. Akad. wiss. Berlin, 1846, and other papers in the same publication in subsequent years.
This is clearly seen by comparing the larva of Asterina gibbosa with a young Bipinnaria in which the longitudinal band is as yet undivided. The shape of the prae-oral lobe is practically the same in both.