The ink sac is a muscular bag which originated as an extension of the hind gut; it is a modified hypobranchial gland.
12.
1 3-to 3 1 / 2-pound octopus ( or 2 1 3 / 4-pound octopuses ), cleaned, trimmed of beak and ink sac
13.
The nib is immersed in ink, the plunger is pushed in, compressing and then releasing the ink sac by means of air pressure.
14.
Although mastigoteuthids possess ink sacs ( which could suggest forays into shallower, lit waters ), all observations have been over the bottom in deep water.
15.
But Palladin made it his business to seek out the ingredients he wanted, whether they were monkfish livers, squid ink sacs or anything else that was routinely discarded.
16.
Unlike the belemnites and other cephalopods, modern nautili do not have an ink sac, and there is no evidence to suggest that the extinct forms possessed one either.
17.
Her observations played a key role in the discoveries that belemnite fossils contained fossilised ink sacs, and that coprolites, known as bezoar stones at the time, were fossilised faeces.
18.
The extant genera all possess ink sacs that open into their cloacae from which they can produce a cloud of black ink when threatened ( as in many cephalopods ).
19.
In 2008, an excavation team led by the British Geological Survey in Christian Malford recovered fossilized ink sacs from several remarkably preserved remains of " Belemnotheutis antiquus " in the Oxford Clay.
20.
The ink is released from the ink sacs ( located between the gills ) and is dispersed more widely when its release is accompanied by a jet of water from the siphon.
