(Chapter 5) Footnote 7:

In this skull, the normal temporal bone suture is absent, as is the medial sagittal suture, which is replaced by an unlikely bilateral (?) anterior-posterior suture from glabella to occipital protuberance (greater occipital eminence). There is an unusual L-shaped suture between the zygomatic and maxillary bones, and the lateral orbit is irregularly shaped. The normally flat or slightly convex surface of the temporal bone is replaced by a more convex shape. It is slightly macrocephalic.

All shapes of the skull illustrated in this chapter appear to be within the range of normal anatomic variation. Also, no skull appears to be more than two standard deviations above or below the mean for maximum fronto-occipital circumference. The reader’s observation is, of course, limited by the fact that no frontal view (norma facialis) is illustrated for any skull. The first drawing does appear to be that of a European skull that falls within the average, “natural,” (mesaticephalic) range for the cephalic index. Other “unnatural” features, particularly the configuration of sutures on skulls 2-5, are probably fanciful, as both Fallopius and Eustachius would protest (see Hall 1911 below).

On Vesalius’ classification of skulls, see M. Hall, “Die Kraniologie Vesals,” Arch. Gesch. Med., 1911, 4: 431-440; W.L. Strauss, Jr. and O. Temkin, “Vesalius and the Problem of Variability,” BullHistMed 14.5 (Dec. 1943), 609-33, esp. pp. 630-32: “For Vesalius, there is only one ‘natural’ form of skull, all variants therefrom being regarded as unnatural. ... Here we see the teleological attitude toward variability ... carried to its logical conclusion.”