With the talk of gathering hair from our pets, it brought to mind the famous, or infamous, Tup's Indispensible. I believe it called for yellowish fur from a spaniel, however, the most secret and difficult to obtain ingredient was the tup's wool which was obtained from the private area of a male sheep. (Try collecting some of that!) The male sheep called a Tup was dyed by the farmer in and about the business area of the sheep, and this way the farmer could tell which female sheep had been serviced by the tup.
The testicle wool was the most desirable wool, and it was the secret ingredient to the original pattern, which was developed by R.S. Austin, with input from G.E.M. Skues. The fly, originally tied as a dry fly, became very popular, and supposedly was very productive. Austin kept the mixture as a secret, and tied and sold only this fly. It was developed into a "nymph" by Skues, which later became a wingless wet fly.
The mix was the Tup's wool, lemon yellow spaniel fur and red mohair-for which Skues substituted red seal fur. It was Skues that also gave the pattern its name. Over the years many speculated as to what the tup's mix was, and there were many variations of the mix.
I tie the fly using a mix of red and yellow seal fur mixed with some pale tan hare's mask fur, guard hair removed. It's a pretty good variation.
Just thought those who collect pet fur might find this an interesting bit of info. Have fun collecting!
Mark