Amazing Spider-Man (1963 1st Series) #81

First appearance of the Kangaroo in "The Coming of the Kangaroo!" Plot by John Romita. Script by Stan Lee. Art by John Buscema (layouts) and Jim Mooney (finishes). Cover by John Romita.

The wondrous wall-crawler rushes to Penn Station to meet Aunt May -- who is returning to New York after her vacation in Florida. Following a quick change of clothes, Peter greets his aunt on the platform...and then observes a disturbance nearby! A large man from Australia leaps away from two federal marshals...and escapes into the streets! Peter can't pursue him right now, but he will tangle with the Kangaroo very soon! The super-villain from down under is looking for money, but he accidentally steals a vial of deadly bacteria instead. So when the web-slinger catches the Kangaroo, he must be very careful with his Australian adversary! Good luck mate! Origin of the Kangaroo. 

32 pages. Cover price $0.15.