Poll Pets poll ETA, 14:10 CST Sat 22 Nov 2008 -
gondhir correctly points out that molluscs (including snails, slugs, and clams) are not arthropods, nor are annelids (worms).
For the first three questions. snails and other molluscs belong under "anything else".
For the last question, the category "Crustacean (crab, lobster, "Sea Monkeys" or other brine shrimp), mollusc (snail, giant oyster) or other non-insect, non-arachnid arthropod (centipede, millipede, etc.)" should be "Other Arthropods, Molluscs, and Annelids", my idea being "other shelled, creepy, crawly, and slimy things that aren't proper bugs (insects and arachnids)". Of course, the line between centipedes and other bugs is pretty fine as pets go; you'd have to define "proper bugs" as "having 6-8 legs".
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Banazir