THE HOTHOUSE BYTHE EAST RIVER by MURIEL SPARK 134 pages. Viking. $5.95.
Muriel Spark has posed in a fetching peignoir with a sinister black cat draped over her shoulder. In her prose, too, she has mostly worn her rue with a deference to the reader's need to take his shots of cold mortality with a little sweet vermouth. Lately, however, the author has grown more flatly somber, shorter on style, wit and patience, like a lonely spinster who has become too preoccupied, too saddened by the world to go through the reassuring motions of genial small talk.
The Driver's Seat (1970) followed a...