In this chapter, Dr. Lanyon has to go to Jekyll's place and get some stuff and bring it back to his own house where someone will meet him. The "someone" turns out to be Mr. Hyde.
As Dr. Lanyon first meets Mr. Hyde, he is really quite disgusted. He is not sure exactly why, but he really dislikes Hyde at first sight. He thinks it is partly because Hyde has some pretty strange physical or medical characteristics. It is also because Hyde is quite small and is wearing really nice clothes that are way too big for him.
So he really just thinks Hyde is just too different and he is repelled by him.