Does it have a "full seat"? As in a line from the back of your calf to your but and back down the other leg? If so, they are the trophy hunter breech. If they do not have that, they are the classic tailoreds.
Are they low-rise or a classic fit? That's another simple way to narrow it down. Compare the material to other breeches you have as well (if you have others) to try and distinguish fabric if you want. One option may be to compare the descriptions of TS breeches online or in a catalog to what you have. Good luck!