Hello Folks.
Its very hard to tell, still from your piccies M8, and the amount of information you've given.
If they're only 40 and 20 days old, how long ago did you put them to flower? if you have put them into flowering, you've done it too early in my oppinion, they really need more vegging, or you'll be very sad with the yield. and if you've not yet put them to flower then you can't know how theyre gonna turn out yet.
Unless you've done it early, to just sex em, then return em to vegging, but I some how doubt that, because your on about keeping males, get the fuck shot of any males, as soon as you know for sure, (unless your raisng males for breeding obviously).
BTW, all the other three guys are right.
And yes, what light are you using, they do look somewhat stretchy, wow if you flower em now you'll end up with a lolipop.
And next time remember, the better the piccs, and the more info you give the more likely someone will be able to help you, and the answers will be more acurate too.
Toodle Ooo.
Martian