The animal of this exquisite shell is a near relative of the octopus. It is similar to the octopus in most respects, except that the female produces the delicate, pure white embossed shell which at times reaches a size of 10 in. The shell is exclusive to the female and she uses it to house the egg mass. The male Argonauta is completely overshadowed by the female, for he is only about an inch in length and does not possess a shell.
These shells are scarcely ever seen on mainland beaches, but at times they are found in considerable numbers on off-shore islands.
by Arthur William Baden Powell, Assistant Director, Auckland Institute and Museum.