Fantastic Beasts And Where To Find Them - The 53th Edition!
When J.K Rowling the book, she forgot to add the Bogart!(which is mentioned in the Prisoner of Azkaban) It says in the book that whenever they find a new beast they release the book again with the new beast information. It looks like they need a new book already!
Did you ever think about the fact that the edition that Harry owns might not be the most recent one? I noticed a few other creatures that weren't in there either, but I can't think of any off the top of my head.
So since J.K. Rowling, like other writers, must be infallible, this is horrible. I must point out that on page 130 of "Harry Potter and the Prisoner of Azkaban," Professor Lupin begins the lesson by saying, and I quote, "Would you please put all your books back in your bags. Today's will be a practical lesson. You will need only your wands." Since they do not need the book, maybe the information necessary is not in the edition.
You need to go back and re-read Fantastic Beasts And Where To Find Them. As this is supposed to be a reproduction of Harry's text NOT an actual text printing then who is to say when they (The Muggle printers) set up the printers they didn't make mistakes and leave out some important information?
Who is to say that as a student's text book there wasn't a page or two missing through neglect or damage? After all, Harry and Ron didn't look after the book too well. Look at all the writing they scribbled all over the book.
As for the book having all the creatures in order, I highly doubt the Muggle printers kept the same size pages or for that matter, made sure everything was EXACTLY the same as in the text. After all, wizard pictures move and how would a Muggle printing reproduce that? So, with the Muggle printer using different size type, different size paper and making allowances for things they can't reproduce like the moving pictures, it makes sense that torn out page or two could get over-looked while copying this text book.
Theres also the fact that this book was made for comic relief, probably made quite quickly, isnt particularly lengthy, or well structured as a textbook. Plus, the ever expanding HP universe is getting quite large, give Rowling a break!