Two groups well i think the answer you wanted to hear was Saurichia and Ornithichia...i think thats the answer you wanted....
Well let me explain Saurichia the group that falls into most of the herbivorious dinos also known as the lizard hip dinos...as the hip bone was lizard like.....Ornithichia...refers to the bird hiped dinos wich fell mostly into the carnivorous and omnivorous dinos. That about gives you a fast discription