The book has no illustrations or index. Purchasers are entitled to a free trial membership in the General Books Club where they can select from more than a million books without charge. Subjects: Fiction / Science Fiction / General; Science / Life Sciences / Biology / General; Science / Life Sciences / Cytology; Science / Life Sciences / Evolution; Science / Life Sciences / Biology / Microbiology; Science / Life Sciences / Biology / Molecular Biology; Science / Life Sciences / General;