It’s spinning time!
The worms have started to convert to spinning. They spend a few hours not eating, then dump out any undigested food, and become spinners. The worm in front has changed over; the one behind has not. They lose quite a bit of length when they make the conversion, because they have downsized their digestive organ systems to make way for the new ones coming in.
The worms will wander about at this stage. Once they find a nice spot (this is in a toilet paper tube, which works great for spinning), they will start laying long loose strands of silk to anchor the cocoon to. This silk is called cocoon strippings, blaze, or keba, and is used in making spun silk. If they are in open trays, the worms can sometimes crawl out and up into inconvenient places, like draperies or the corners of walls.
The worm has now gotten a good start – the cocoon is nearly opaque now, although it will continue to get thicker and more solid. Spinning will continue on the inside for up to three days; after it is completed, the worm will cast off its final caterpillar skin and change to a pupa.
Here, held against a strong backlight, you can see the worm inside still spinning.
I know I’ve said this before but let me say it one more time. These updates are incredible. Thank you so much for posting them.
I actually just said, “yay, new pictures!” I love these posts.
I’m glad you enjoy them! I keep forgetting to update here so if I miss several days, check wormspit.com – it can get kind of complicated to try and remember to keep two sets of updates going!
Well, thanks! I am sure enjoying sharing the whole process.
Re: Silkworm updates!
the intricate biology of these silkworms is just fascinating.
This is really great! I really think you should definitely do a book!
I must admit, I’ve spent many hours at work looking at the pictures of your website. The last time my boss caught me looking at wormspit.com he walked by and said, “Not thinking of raising silkworms now are ya?” I thought he’d tell me to get back to work.
Nope, no silkworm raising. I’m into kid-raising at the moment. 7-1/2 more years and he pops out of his cocoon!