So much for the copulations of such animals as copulate.

We now proceed to treat of generation both with respect to
copulating and non-copulating animals, and we shall commence with
discussing the subject of generation in the case of the testaceans.

The testacean is almost the only genus that throughout all its
species is non-copulative.

The porphyrae, or purple murices, gather together to some one
place in the spring-time, and deposit the so-called 'honeycomb'.
This substance resembles the comb, only that it is not so neat and
delicate; and looks as though a number of husks of white chick-peas
were all stuck together. But none of these structures has any open
passage, and the porphyra does not grow out of them, but these and all
other testaceans grow out of mud and decaying matter. The substance,
is, in fact, an excretion of the porphyra and the ceryx; for it is
deposited by the ceryx as well. Such, then, of the testaceans as
deposit the honeycomb are generated spontaneously like all other
testaceans, but they certainly come in greater abundance in places
where their congeners have been living previously. At the commencement
of the process of depositing the honeycomb, they throw off a
slippery mucus, and of this the husklike formations are composed.
These formations, then, all melt and deposit their contents on the
ground, and at this spot there are found on the ground a number of
minute porphyrae, and porphyrae are caught at times with these
animalculae upon them, some of which are too small to be
differentiated in form. If the porphyrae are caught before producing
this honey-comb, they sometimes go through the process in
fishing-creels, not here and there in the baskets, but gathering to
some one spot all together, just as they do in the sea; and owing to
the narrowness of their new quarters they cluster together like a
bunch of grapes.