There's a difference between anatomical loins and a butcher's cut of loins.
The pic is kinda right for the position of a buther's cut of the loin, at least in beef and pork. But in terms of anatomy, the loin is another name for your groin (and ribs, and lower back).
Saying that, that pic is all over the place in terms of it's labels... You shouldn't find both rump and round on the same animal, one's American the other's British. (In the US there are three or four different cuts for the loin - Top, Bottom, silver and sir, to name a few, while in the UK that'd the Sirloin and that's it. Also what an American would call the round would be sold here as either rump, silverside and/or topside). But's that's only in beef or pork, as far as I know... I dunno about poultry.. Also, I'm pretty sure you'd only get breast off of poultry anyhow, that area in a cow is the brisket, and I think it's actually part of the shoulder in pork.