I found this stuck to my trousers and i dont know what it is or were it comes from,but i like to know what it is, i live in Galway Ireland, kind regards
Your caterpillar is a Puss Moth Caterpillar, Cerura vinula. The UK Moths site indicates that the common name comes from the moths resemblance to a cat. The caterpillar feeds on willow, poplar and aspen. Artist Katherine Plymley has a metamorphosis watercolor reproduced online.