by RUSSELL HOBAN 211 pages. Random House. $7.95.
Two lonely fortyish souls walk their depressions around London. William is a bookstore clerk who has shed most of his past, including a cushy job in advertising, his wife and two daughters.
Neaera writes and illustrates children's books but she has grown tired of creating furry and feathery characters: perversely, she ponders a new story about a water beetle. Both visit the London Zoo and independently reach the same conclusion: the sea turtles in the aquarium must be liberated and allowed to swim back to their breeding grounds in the Atlantic.
Were this carapace...