Hornets is a derivative of Galaxian, but with some twists. There is a "track" (their nest) at the top of the screen that the hornets rotate around (rather than flying in formation, like the arcade original), but if you take too long to kill them, they become angry and disembark and fire stings at you (they also completely change shape, to the vaguely V-shaped cyan thing you can see on the bottom left of the 3rd screenshot above). There are three other interesting twists, compared to Galaxian: 1) The hornets, once they dive bomb, will dive bomb continuously until destroyed. 2) The more of the hornets you kill, the faster the remainder of them go. 3) Only one hornet appears to be able to divebomb at a time.
This was ported from the Dragon 32. It was part of Games pack 4 that also contained Pterodactyl and Torpedo Run.
Title: Hornets
Author: John Morrison
Publisher: J. Morrison (Micros)
Released: July 1983 (Dragon release)
Requires: Color Computer 1,2,3, 16K RAM, cassette or disk.