October 30, 1903.] 



SCIENCE. 



551 



tliree points was chosen, and caeh point, 

 would be about the same distance from the 

 brain. ^Vith the appearance of the teeth 

 of the second dentition and the enlarge- 

 ment of the jaws the frontal bone in the 

 region of the eyebrows and just above the 

 root of the nose thickens, and its outer 

 table bulges forward so that it is now no 

 longer parallel with the inner table. Be- 

 tween these tables air cavities gradually ex- 

 tend from the nose, fornung the frontal 

 sinuses. Although the existence and sig- 

 nificance of these spaces and their influence 

 on the prominence of the eyebrows were 

 the subject of a fierce controvei-sy more 

 than half a century ago between the 

 phrenologists and their opponents, it is 

 only recently that their variations have 

 been carefully investigated. 



The frontal sinuses are usually supposed 

 to vary according to the degree of prom- 

 inence of the glabella and the supra-orbital 

 arches. This, however, is not the case. 

 Thus Schwalbe* has figured a skull in 

 which the sinuses do not project as high 

 as the top of the glabella and supra-orbital 

 prominences, and another in which they 

 extend considerably above these pi-ojec- 

 tions. Further, Dr. Logan Turner ('The 

 Accessory Sinuses of the Nose,' 1901), who 

 has made an extensive investigation into 

 these cavities, has shown that in the aborig- 

 inal Au.stralian, in whom this region of the 

 skull is unusually prominent, the frontal 

 sinuses are frequently either absent or 

 rudimentarj'. The ophryon has been 

 selected by some craniologists as the an- 

 terior point from which to measure the 

 length of the skull, under the impression 

 that the frontal sinuses do not usually reach 

 above the glabella. Dr. Logan Turner, 

 however, found that out of 174 skulls in 

 which the frontal sinuses were present, in 



* ' Studien fiber Pithecanthropus erectus,' Zeit- 

 schrift fiir Morphologic und Anthropologic, Bd. 



1.. isnn. 



l:!0 the sinuses extended above the ophryon. 

 In 71* skulls the depth of the sinus at the 

 level of the ophryon varied from 2 mm. to 

 16 nuu., the average being 5.2 mm., while 

 in the same series of skulls the depth at 

 the glabella varied from 3 mm. to 18 mm., 

 with an average depth of 8.5 mm. It thus 

 appears that the selection of the ophryon in 

 preference to the glabella, as giving a more 

 accurate clue to the length of the brain, 

 is based upon erroneous assumptions, and 

 that neither point can be relied upon in the 

 determination of the anterior limit of the 

 cranial cavity. 



The difficulties of estimating the extent 

 of the cranial cavity by external measure- 

 ments and the fallacies that may result 

 from a reliance upon this method are es- 

 pecially marked in the case of the study 

 of the prehistoric human calvaria, such as 

 the Neanderthal and the Trinil. and the 

 skulls of the anthropoid apes. 



Statistics are popularly supposed to be 

 capable of proving almost anything, and 

 certainly if you allow craniologists to select 

 their own points from which to measure 

 the length and breadth of the cranium, 

 they will furnish you with tables of meas- 

 urements showing that one and the same 

 skull is dolichocephalic, mesaticephalic and 

 braehycephalie. Let us take as an illustra- 

 tion an extreme case, such as the skull of 

 an adult male gorilla. Its glabella and 

 supra-orbital arches will be found to pro- 

 ject forward, its zygomatic arches out- 

 wards, and its transverse occipital crests 

 backwards, far beyond the anterior, lateral 

 and posterior limits of the cranial cavity. 

 These outgrowths are obviouslj- correlated 

 with the enormous development of the mus- 

 cles of mastication and tho.se of the back 

 of the neck. In a specimen in my posses- 

 sion the greatest length of the cranium, 

 i. e., from glabella to external occipital 

 protuberance, is 195 mm., and the greatest 



