The squid giant axon is a very large axon in the body of a regular squid (not giant squid, despite the name). It is about 0.5 mm in diameter and useful for electrophysiology experiments.
Do we have any measurements about how big it is in the actual giant squid and the even larger colossal squid? I’d imagine they’re pretty decayed when we get them but it seems someone couldn’t measured. My googling isn’t stacking up.
Looking forward to seeing a substantive answer, and just popping in to observe that this is a contender for most ominous username/post combo., and definitely wins the title for most ominous username/OP combo.
If anyone want to shell out $450 for this book, the answer is within 
Based on some cursory Googling, I found the following quote from that book:
“Each stellar nerve contains one or more giant fibres reaching 300 micrometers, but most are smaller.”
This is referring to Mesonychoteuthis (the Collossal Squid). Architeuthis (Giant Squid) axons apparently fall below 260 micrometers, so both Giants and Collossals appear to have smaller nerve axons than their smaller cousins.
Finch beat me to it; giant squid have giant axons, but not giant giant axons.
Video of a public dissection of a giant squid here.
This says the Humboldt Squid goes up to 1.5 mm.
Thanks. My prize is all your souls. For the nomination, Polycarp will be eaten last.
I wonder why the size is inverse. I think these are unmyelinated, so I might speculate that larger diameter = more surface area and thus more decrement in the electrical potential. By limiting size, they limit leakage. However, I may be talking out of my ass, I would like to know what those books say, but I am not shelling out $450.
Interlibrary loan, my friend. I’m always surprised at how many people don’t know what their local library will get them, often for free and if anything for the cost of shipping.
You could try reading my link.
Look, I appreciate the link, but it often helps to give an answer or at least a page number if info is contained within. Saying “lrn 2 read plz” while providing a link with several pages missing, technically about the wrong species, isn’t terribly helpful right now.
I’ve seen the animated documentaries. If they’re anything to go by, then their axons must be huge!