„ „ Observations on the development of the pond-snail (Lymnaeus stagnalis), and on the early stages of other Mollusca: Quart. Journ. Micr. Sc. xiv. (1874), pp. 365–391.
„ „ Observations on the development of the Cephalopoda: ibid. xv. (1875), pp. 37–47.
W. Patten, The embryology of Patella: Arb. Zool. Inst. Univ. Wien, vi. (1886), pp. 149–174.
M. Salensky, Études sur le développement du Vermet: Arch. Biol. vi. (1885), pp. 655–759.
L. Vialleton, Recherches sur les premières phases du développement de la Seiche (Sepia officinalis): Ann. Sc. Nat. Zool. (7) vi. (1888), pp. 165–280.
S. Watase, Observations on the development of Cephalopods: Stud. Biol. Lab. Johns Hopk. Univ. iv. (1888), pp. 163–183.
„ „ Studies on Cephalopods: Journ. Morph. iv. (1891), pp. 247–294.
E. Ziegler, Die Entwickelung von Cyclas cornea Lam.: Zeit. wiss. Zool. xli. (1885), pp. 525–569.
CHAPTER VI
RESPIRATION AND CIRCULATION—THE MANTLE
The principle of respiration is the same in the Mollusca as in all other animals. The blood is purified by being brought, in successive instalments, into contact with pure air or pure water, the effect of which is to expel the carbonic acid produced by animal combustion, and to take up fresh supplies of oxygen. Whether the medium in which a mollusc lives be water or air, the effect of the respiratory action is practically the same.