you're lucky, the only one I could find had parasites on it

Their appetites and growth rates are enormous, Madam Butterfly! I usually find some clean, dry topsoil, without ants or other varmits, put it in my old terrarium, put some clean, dry leaves over that, and put the cats in the terrarium when they're ready to pupate, that is, when they've gotten huge, they've emptied their bowels big time and turned a slightly yellowy, peachy color.
Did you bring your cats in from outside? I brought my cats into a cage from outside on the vines as soon as I found them - most of them were still very small, but a few were probably middle instar cats. My first emerger was a Carolina sphinx moth, but after that, there were several batches of tachinid flies that came out, and I do mean big batches! I had thought that since I couldn't see any of those white wasp cocoons, my cats were unparasatized - was I wrong! Apparently, you can't tell when cats have been parasatized by tachinid flies.
Tomato/tobacco hornworm cats get the most parasites of any cat I know of. I won't raise any more except from eggs - hopefully, the eggs can't be parasitized!
Sherry

This is perfect timing for me. My son and I want to bring in a hornworm egg but I wasn't sure how to handle the whole pupating issue. I like the terrarium idea. I will need to get one. But what about temperature? After they pupate, can we keep it in the basement? I have had cats, cocoons, butterflies and moths on my counter all summer and I would hate to have to make room for a large container of dirt. When should we look for the moth so we don't miss it?

Thanks, Ann

I don't know what the cold (or heat) tolerance is for tomato/tobacco hornworms, Ann, but generally speaking, all chrysalids or cocoons overwinter well in cold but not freezing conditions. I keep mine in my unheated guest room, where the temps vary from about the upper 40's or lower 50's on the coldest nights to the upper 60's, maybe low 70's sometimes. When spring starts to arrive and plants start leafing out, I bring my cocoons/chrysalids onto the porch outside, and they start emerging. By putting the terrarium in a cage, I get to see the moths that burrow before releasing them, too.
What's the humidity like in your basement? I've never been in one. I'd think it'd be VERY damp. Cocoons/chrysalids shouldn't dry out, but they also shouldn't get moldy. Mold is probably the one drawback to putting them in a basement, but you know the conditions there better than I do.
Sherry

I don't think my basement is that damp but maybe the garage would be better. Although the egg hasn't even hatched yet:)

Ann

keep an eye out for more eggs

Shhhhhhh dont tell my parents but I've been able to smuggle a healthy one into my bedroom butterfly cage YAY

I have raised some caterpillars indoors and some outside. In my own experience, they do better outside where the temps are what they are..... Transferring them indoors to a/c and other fluctuating temps seemed to do more harm than good to them. I'm talking the big cats, like the tobacco/tomato/eumorphas. The smaller moth cats, like the clearwings, seemed to do fine indoors and I overwintered them in containers in my veggie compartment in the fridge. I brought them out in April (early), pulled all the toweling (paper towels is what I use in my moth containers indoors, shredded up and they make their cocoons inside pieces of the toweling), and put some sticks in a tall plastic container. This way, when they emerge, they can climb up on the sticks to fully inflate their wings.

Funny thing, just this morning I saw a HUMONGOUS eumorpha achemon on the Virginia Creeper (dark brown with the white spots; no horn because they lose their horns in 3-5th instar of growth). He was not parasitized so I left him alone on the VC and hope he will be just fine.

I've also used potting soil in the bottom of containers and just stuck stems of tomatoe or datura (they will eat both), and the moths then burrow underground to make their cocoons. These containers, I leave outside on the porch during winter so they will remain in diapause until ready to emerge next spring. I had one Walnut Sphinx that stayed underground all winter and emerge in spring. I had forgotten about it, so it died waiting for me to release it (so sad; bad me).

As MissSherry says, these big ole hornworms tend to be very popular with the predatory wasps/flies. My tobacco hornworm I rescued this month had absolutely no indications of paritisation, but the following morning it was hanging limp on a branch of the datura I found it on. There was absolutely no sign of parasite damage. Sometimes there will be little black spots or holes that indicate the emergence of a parasitic wasp/fly, but there was absolutely nothing to mar the poor baby.

Good luck - they are fun to raise, and kids usually adore them.

Susan