ABSTRACT
The material upon which I have made my investigations was in part collected by me in N. Celebes, and in part by Professor A. C. Haddon in Torres Straits. Some of the specimens were treated with strong alcohol alone, others with corrosive sublimate followed by alcohol. For decalcification I have entirely used nitric acid.
I take the account of Kupffer’s work from the paper of van Beneden and Julin (2, p. 430). I regret that I have been unable to refer to Kupffer’s original paper.
As Kowalewsky’s paper is written in the Russian language I am unable to read it.
It is a noteworthy point that O. von Rath (48), who believes that the nuclei of the spermatogonia and spermatocytes always divide mitotically, does not refer at all in his paper to the spermatogenesis of Polychætes.
