knobbed argonaut (Argonauta nodosa), ram's horn squid (Spirula spirula) Argonauta nodosa = knobbed argonaut (Argonauta nodosa)
Spirula peroni = Spirula peronii = ram's horn squid (Spirula spirula)
Title: Beautiful shells of New Zealand : an illustrated work for amateur collectors of New Zealand marine shells, with directions for collecting and cleaning them / by E.G.B. Moss ; photographs by C. Spencer.
Author: Moss, E. G. B. (Edward George Britton Moss)
Publication info: Auckland :Collins Bros.,1908.
Subjects: Collection and preservation; Mollusks; New Zealand; Shells
Source: http://www.biodiversitylibrary.org/page/13064328#page/55/mode/1up
The knobby argonaut or knobbed argonaut (Argonauta nodosa) is a species of pelagic octopus. The female of the species, like all argonauts, creates a paper-thin eggcase that coils around the octopus much like the way a nautilus lives in its shell (hence the name paper nautilus).
The ram's horn squid (Spirula spirula) is a species of deep-water squid-like cephalopod mollusk. It is the only extant member of the genus Spirula, the family Spirulidae, and the order Spirulida. Because of the shape of its internal shell, it is commonly known as the ram's horn squid or the little post horn squid. Because the live animal has a light-emitting organ, it is also sometimes known as the tail-light squid.