The latest of the Selsam-Hunt primer exercises in classification follows the series pal tern, beginning with the features that distinguish spiders from other animals (""Is this a spider? Count the legs. There are six. Count the body parts. There are three. It is not a spider. It is an insect""), then going on to distinguish certain spiders from others. Thus there are hunting spiders and web-spinning spiders, and subdivisions of each, with distinguishing webs for different web spinners and pictures to match up with the descriptions: ""Find the web that looks like a sheet. Find the web that looks tangled,"" and so on. After this Selsam introduces the large tarantulas, who belong to a ""separate group"" distinguished by their up-and-down jaws and called here by the jaw-breaking name mygalomorphs. More limited in scope than most in the series and pedestrian as a first book on spiders, this is probably best suited as reinforcement for the series concept--where the series is used that exhaustively.