 The book was intended as an update in medical thinking (a century later) about anatomy.In his 1624 treatise "De semitertiana libri quatuor", he gave the first comprehensive description of malaria.His name is given to the Spiegelian line (Linea semilunaris) and the Spiegelian fascia, which refers either to the combined aponeuroses of the external abdominal oblique muscle, the internal abdominal oblique muscle and transversus abdominis muscle, or just the aponeurosis of the transversus abdominis.