on some fossil remains of man-第7节

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become　more　obtuse；　and　that　the　'cranio…facial　angle'　becomes　more
acute　by　the　bending　down；　as　it　were；　of　the　facial　axis　upon　the
cranial　axis。　　At　the　same　time；　the　roof　of　the　cranium　becomes　more
and　more　arched；　to　allow　of　the　increasing　height　of　the　cerebral
hemispheres；　which　is　eminently　characteristic　of　man；　as　well　as　of
that　backward　extension；　beyond　the　cerebellum；　which　reaches　its
maximum　in　the　South　America　Monkeys。　　So　that；　at　last；　in　the　human
skull　（Fig。　29）；　the　cerebral　length　is　between　twice　and　thrice　as
great　as　the　length　of　the　basicranial　axis；　the　olfactory　plane　is　20
degrees　or　30　degrees　on　the　'under'　side　of　that　axis；　the　occipital
angle；　instead　of　being　less　than　90　degrees；　is　as　much　as　150　degrees
or　160　degrees；　the　cranio…facial　angle　may　be　90　degrees　or　less；　and
the　vertical　height　of　the　skull　may　have　a　large　proportion　to　its
length。

It　will　be　obvious；　from　an　inspection　of　the　diagrams；　that　the
basicranial　axis　is；　in　the　ascending　series　of　Mammalia；　a　relatively
fixed　line；　on　which　the　bones　of　the　sides　and　roof　of　the　cranial
cavity；　and　of　the　face；　may　be　said　to　revolve　downwards　and　forwards
or　backwards；　according　to　their　position。　　The　arc　described　by　any
one　bone　or　plane；　however；　is　not　by　any　means　always　in　proportion　to
the　arc　described　by　another。

Now　comes　the　important　question；　can　we　discern；　between　the　lowest　and
the　highest　forms　of　the　human　cranium　anything　answering；　in　however
slight　a　degree；　to　this　revolution　of　the　side　and　roof　bones　of　the
skull　upon　the　basicranial　axis　observed　upon　so　great　a　scale　in　the
mammalian　series？　　Numerous　observations　lead　me　to　believe　that　we　must
answer　this　question　in　the　affirmative。

The　diagrams　in　Figure　29　are　reduced　from　very　carefully　made　diagrams
of　sections　of　four　skulls；　two　round　and　orthognathous；　two　long　and
prognathous；　taken　longitudinally　and　vertically；　through　the　middle。
The　sectional　diagrams　have　then　been　superimposed；　in　such　a　manner；
that　the　basal　axes　of　the　skulls　coincide　by　their　anterior　ends；　and
in　their　direction。　The　deviations　of　the　rest　of　the　contours　（which
represent　the　interior　of　the　skulls　only）　show　the　differences　of　the
skulls　from　one　another；　when　these　axes　are　regarded　as　relatively
fixed　lines。

The　dark　contours　are　those　of　an　Australian　and　of　a　Negro　skull：　the
light　contours　are　those　of　a　Tartar　skull；　in　the　Museum　of　the　Royal
College　of　Surgeons；　and　of　a　well　developed　round　skull　from　a
cemetery　in　Constantinople；　of　uncertain　race；　in　my　own　possession。

It　appears；　at　once；　from　these　views；　that　the　prognathous　skulls；　so
far　as　their　jaws　are　concerned；　do　really　differ　from　the
orthognathous　in　much　the　same　way　as；　though　to　a　far　less　degree
than；　the　skulls　of　the　lower　mammals　differ　from　those　of　Man。
Furthermore；　the　plane　of　the　occipital　foramen　（'b　c'）　forms　a
somewhat　smaller　angle　with　the　axis　in　these　particular　prognathous
skulls　than　in　the　orthognathous；　and　the　like　may　be　slightly　true　of
the　perforated　plate　of　the　ethmoidthough　this　point　is　not　so
clear。　　But　it　is　singular　to　remark　that；　in　another　respect；　the
prognathous　skulls　are　less　ape…like　than　the　orthognathous；　the
cerebral　cavity　projecting　decidedly　more　beyond　the　anterior　end　of　the
axis　in　the　prognathous；　than　in　the　orthognathous；　skulls。

It　will　be　observed　that　these　diagrams　reveal　an　immense　range　of
variation　in　the　capacity　and　relative　proportion　to　the　cranial　axis；
of　the　different　regions　of　the　cavity　which　contains　the　brain；　in　the
different　skulls。　　Nor　is　the　difference　in　the　extent　to　which　the
cerebral　overlaps　the　cerebellar　cavity　less　singular。　　A　round　skull
（Fig。　29；　'Const'。）　may　have　a　greater　posterior　cerebral　projection
than　a　long　one　（Fig。　29；　'Negro'）。

Until　human　crania　have　been　largely　worked　out　in　a　manner　similar　to
that　here　suggesteduntil　it　shall　be　an　opprobrium　to　an　ethnological
collection　to　possess　a　single　skull　which　is　not　bisected
longitudinallyuntil　the　angles　and　measurements　here　mentioned；
together　with　a　number　of　others　of　which　I　cannot　speak　in　this　place；
are　determined；　and　tabulated　with　reference　to　the　basicranial　axis　as
unity；　for　large　numbers　of　skulls　of　the　different　races　of　Mankind；　I
do　not　think　we　shall　have　any　very　safe　basis　for　that　ethnological
craniology　which　aspires　to　give　the　anatomical　characters　of　the　crania
of　the　different　Races　of　Mankind。

At　present；　I　believe　that　the　general　outlines　of　what　may　be　safely
said　upon　that　subject　may　be　summed　up　in　a　very　few　words。　　Draw　a
line　on　a　globe　from　the　Gold　Coast　in　Western　Africa　to　the　steppes　of
Tartary。　　At　the　southern　and　western　end　of　that　line　there　live　the
most　dolichocephalic；　prognathous；　curly…haired；　dark…skinned　of
menthe　true　Negroes。　　At　the　northern　and　eastern　end　of　the　same
line　there　live　the　most　brachycephalic；　orthognathous；
straight…haired；　yellow…skinned　of　menthe　Tartars　and　Calmucks。　　The
two　ends　of　this　imaginary　line　are　indeed；　so　to　speak；　ethnological
antipodes。　　A　line　drawn　at　right　angles；　or　nearly　so；　to　this　polar
line　through　Europe　and　Southern　Asia　to　Hindostan；　would　give　us　a
sort　of　equator；　around　which　round…headed；　oval…headed；　and
oblong…headed；　prognathous　and　orthognathous；　fair　and　dark　racesbut
none　possessing　the　excessively　marked　characters　of　Calmuck　or
Negrogroup　themselves。

FIG。29。Sections　of　orthognathous　（light　contour）　and　prognathous　（dark
contour）　skulls；　one…third　of　the　natural　size。　　'a　b'；　Basicranial
axis；　'b　c；　b1　c1'；　plane　of　the　occipital　foramen；　'd　d1'；　hinder　end
of　the　palatine　bone；　'e　e1'；　front　end　of　the　upper　jaw；　'T　T1'；
insertion　of　the　tentorium。

It　is　worthy　of　notice　that　the　regions　of　the　antipodal　races　are
antipodal　in　climate；　the　greatest　contrast　the　world　affords；　perhaps；
being　that　between　the　damp；　hot；　steaming；　alluvial　coast　plains　of
the　West　Coast　of　Africa　and　the　arid；　elevated　steppes　and　plateaux　of
Central　Asia；　bitterly　cold　in　winter；　and　as　far　from　the　sea　as　any
part　of　the　world　can　be。

From　Central　Asia　eastward　to　the　Pacific　Islands　and　subcontinents　on
the　one　hand；　and　to　America　on　the　other；　brachycephaly　and
orthognathism　gradually　diminish；　and　are　replaced　by　dolichocephaly
and　prognathism；　less；　however；　on　the　American　Continent　（throughout
the　whole　length　of　which　a　rounded　type　of　skull　prevails　largely；　but
not　exclusively）*　than　in　the　Pacific　region；　where；　at　length；　on　the
Australian　Continent　and　in　the　adjacent　islands；　the　oblong　skull；　the
projecting　jaws；　and　the　dark　skin　reappear；　with　so　much　departure；　in
other　respects；　from　the　Negro　type；　that　ethnologists　assign　to　these
people　the　special　title　of　'Negritoes。'

　　　　＇footnote＇　*See　Dr。　D。　Wilson's　valuable　paper　〃On　the
　　　　supposed　prevalence　of　one　Cranial　Type　throughout　the
　　　　American　aborigines。〃'Canadian　Journal'；　vol。　ii。；　1857。

The　Australian　skull　is　remarkable　for　its　narrowness　and　for　the
thickness　of　its　walls；　especially　in　the　region　of　the　supraciliary
ridge；　which　is　frequently；　though　not　by　any　means　invariably；　solid
throughout；　the　frontal　sinuses　remaining　undeveloped。　　The　nasal
depression；　again；　is　extremely　sudden；　so　that　the　brows　overhang　and
give　the　countenance　a　particularly　lowering；　threatening　expression。
The　occipital　region　of　the　skull；　also；　not　unfrequently　becomes　less
prominent；　so　that　it　not　only　fails　to　project　beyond　a　line　drawn
perpendicular　to　the　hinder　extremity　of　the　glabello…occipital　line；
but　even；　in　some　cases；　begins　to　shelve　away　from　it；　forwards；
almost　immediately。　　In　consequence　of　this　circumstance；　the　parts　of
the　occipital　bone　which　lie　above　and　below　the　tuberosity　make　a　much
more　acute　angle　with　one　another　than　is　usual；　whereby　the　hinder
part　of　the　base　of　the　skull　appears　obliquely　truncated。　　Many
Australian　skulls　have　a　considerable　height；　quite　equal　to　that　of
the　average　of　any　other　race；　but　there　are　others　in　which　the　cranial
roof　becomes　remarkably　depressed；　the　skull；　at　the　same　time；
elongating　so　much　that；　probably；　its　capacity　is　not　diminished。　　The
majority　of　skulls　possessing　these　characters；　which　I　have　seen；　are
from　the　neighbourhood　of　Port　Adelaide　in　South　Australia；　and　have
been　used　by　the　natives　as　water　vessels；　to　which　end　the　face　has
been　knocked　away；　and　a　string　passed　through　the　vacuity　and　the
occipital　foramen；　so　that　the　skull　was　suspended　by　the　greater　part
of　its　basis。

FIG。　30。An　Australian　skull　from　Western　Port；　in　the　Museum　of　the
Royal　College　of　Surgeons；　with　the　contour　of　the　Neanderthal　skull。
Both　reduced　to　one…third　the　natural　size。

Figure　30　represents　the　contour　of　a　skull　of　this　kind　from　Western
Port；　with　the　jaw　attached；　and　of　the　Neanderthal　skull；　both　reduced
to　one…third　of　the　size　of　nature。　　A　small　additional　amount　of
flattening　and　lengthening；　with　a　corresponding　increase　of　the
supraciliary　ridge；　would　convert　the　Australian　brain　case　into　a　form
identical　with　that　of　th