Yes to get bees you need a pastel and a spider.
To get a white snake you need either two lessers, butters, mojave, yellowbelly, russo's, or fires. With the fires the snake is not entirly white it sometimes has some yellow on it. With the lesser and butter they are pretty much the same and make the whitest snake out of all of them. You can interchange the butter, lesser mojave and het russo's to make the blue eyed lucy. Then you have your black eyed lucys which are made with the yellowbellies and fires. So all in all you need to get four snakes to make what you want unless you get a lesser/butter pastel and a lesser/butter spider, then you only need two snakes.
If i was trying to make a white snake i would use lessers or butters they make the cleanest white snake.
Hope this helps