An invading army of millions of tiny toads has taken over the peaceful suburb of Dublin, about 25 miles southeast of San Francisco. The hopping baby toads, who are leaping out of a drainage canal, are winning the hearts of the suburbanites, who have garaged their lawn mowers for the duration and pledged to take special care where they walk and drive. A large female toad can lay 20,000 eggs, most of which usually end up as hors d’oeuvres on up the food chain. The tiny toads started appearing in the neighborhood about two weeks ago. About the size of a dime, the croaking, warty amphibians soon took over streets, roads and yards, unrolling their long, sticky tongues to terminate any incautious bug doodling by on wing or leg. Most will be eaten by birds, raccoons or even neighborhood cats by the end of the summer.