I thought I had checked the Q/A lately, but I have totally overlooked these comments. My apologies.
As an answer: I told you what these monsters were, but I would advise you not to look up their stats. I have implied somewhere that none of you have ever encountered the Ankheg before. Looking up their weaknesses so your character can use them goes against what we're trying to accomplish here. I can understand why you did it though, but such is not really the way to go.

If I tell you the name of a monster, it is so you can maybe get a better picture of him (because you've fought them before in other games perhaps, or because you know them by legend, or just so you can give whatever you are fighting a proper name instead of
'the monster that looks like a giant insect but it's definitely not a spider'.

)
As for your chance of hitting them: you can trust me when it comes to combat. I am on your side and not looking to slaughter players unless they act utterly stupid or unless the dice are persistent in telling me they should receive critical hits. But you can do certain things to help yourself get a certain benefit (by flanking, or trying a shot at one of the creature's eyes f.i, but that is extremely hard).
And in any case, I think that the rulebook you have is an old one, 2nd edition I think, and things have changed since then.
Conclusive: you are free to use your books to look up images of monsters I give you, but please do not check the stats.
Wow, that could've been a lot shorter message after all.
Dragonblood, I will do my best to get a grid up, so you can all see where everybody is standing.