Which is weirder: that there is a source that catalogues the tongues of different animals, or that Charlie Brown is referring to it? If Peanuts were being drawn today, CB would probably be editing a Wikipedia page.
This strip reminds me of a favorite Sunday entry from later in the run, the "Linus is aware of his tongue" strip, that injects just a tiny bit of Lovecraftian biological horror into the cartoon world.
Imperfect circles? This strip is really about defining terms: mathematically, there are only perfect circles, but practically we call all kinds of things circles that aren't precisely obedient to the rules of geometry.
Continuing from last week, more of the "Snoopy gets scratched on the chin" sequence. Charlie Brown's amused smile in the last panel makes this one for me. No one can have a character pass judgment with a simple smile like Charles Schulz can.
Charlie Brown must have rather some serious self-esteem issues here, but really, what kind of insult is "angle worm" anyway. It's got to be a real insult, of that I have no doubt because the joke of the strip relies on the reader having prior knowledge of the term, but it still seems silly, which is probably why it's no longer, to my knowledge, in currency.
Third of the chin-scratching strips. It's okay when Lucy does it, but not when Charlie Brown does? This suggests either that CB has a harsh scratching technique (perhaps clued by the fact that Lucy's "tickles" are in word balloons while Charlie Brown's are without), or that Snoopy gets something out of having his chin scratched by girls.
Oh no, Charlie Brown's been run over by a truck!