It is with regret that we report that Ellen MacGregor, creator of beloved Miss Pickerell, died recently. Always, her books have been models of the kind of humane and humorous fantasy that comes realistically yet lightheartedly to grips with today's world, and she does not fail us here. For Miss Pickerell's latest adventures -- illustrated with dash by Paul Galdone -- take her on a rescue flight north and are full of funny suspense. The set of Pickerellian circumstances that get her there involve a lost weather-study expedition, a new snowmobile trailer she wants for her cow, her niece and nephew who are ham radio operators, etc. etc. Once there and to the rescue, she enjoys herself so well that she is sad to say good-bye to her ""beautiful arctic regions"". We wish it were not goodbye to us.