CEPHALOPODS. 



493 



the spots take the tint of wine lees. When at rest the shades 

 disappear. 



In Pinnoctopus cordiiformis, a member of this family, the body- 

 is oblong, with lateral expansions, as represented in the accompanying 

 figure (Fig. 333). 



In Cirrhothcutis the arms are completely united in their whole 

 extent by a thin membrane furnished with cirri, which alternate with 

 certain suckers arranged in one row. Only one species (C Mullen) 



\ 



Fig. 333. — Pinnoctopus cordiiformls (Q. & G.). Fig. 334. — Cirrhotheutis Mullen (Eschricht) 



of this genera is kno^\^l as an inhabitant of the northern seas, which 

 is represented in Fig. 334. 



The sixth family, Argonautidce, contains only one genus, 

 Argo?iaii.ta. 



Argonauta argiis is the Paper Nautilus. Floating gracefully on 

 the surface of the sea, trimming its tiny sail to the breeze, just 

 sufficient to ruffle the surface of the waves, behold the exquisite living 

 shallop ! The elegant little bark which thus plays with the current is 

 no work of human hands, but a child of Nature : it is the Argonaut, 

 whose tribes, decked in a thousand brilliant shades of colour, are 

 wanderers of the night in innumerable swarms on the ocean's 

 surface ! 



The marine shell which Linnaeus called the Argonaut enjoyed 



