According to page 12 of the manual, the correct spelling is "Pirana plant". The SMB3 manual lists only new enemies. Page 40 lists "The Pirana Plants" and includes "Walking Piranas". It wasn't until Super Mario World that the manual lists a "Jumpin' Piranha Plant" on page 23, with the correct spelling of piranha. In the end credits, it's listed as "Jumping Pirhana Plant".
Also, no "Bowser, King of the Koopa"?
Also, how do you know that it's called a "Turtle Cannon"? It wasn't listed in the manual, and I can't find any online references to it. Everything I've seen calls it a "Bullet Bill Launcher".
Also, apparently, the name Turtle Cannon came from both a Nintendo Power volume and a "How to Win at Super Mario Bros." book. Not sure how canonical these are, but apparently the Mariowiki editors think it's canonical enough.
Also, no "Bowser, King of the Koopa"?
Also, how do you know that it's called a "Turtle Cannon"? It wasn't listed in the manual, and I can't find any online references to it. Everything I've seen calls it a "Bullet Bill Launcher".