548 IV- CONKKIilvNCl': I.NTKIlNATin.NAIJ'. I)K OKNKTUjI K. 



wliicli is a dominanl cliarjulci-. Inin rilcd ili-cM.-cs llial licliaxc as dominanl 

 charactcrs, arc ralarari ( .\rlllr<lii|i). Kcmloxix /m/uuiris cl plmilariK, and 

 llercdilarij Chorea. As regards llic lai Ut discasi', lin- proi^ciiN IVimi llie 

 nialings of lielcrozygous individiials, willi iioniial iiidividiials, i^avc llic lolals 

 1 17 allecled, 9!) unaH'ected (Ijaleson). A certain nuinbcr of diseases arc consi- 

 dercd by (iossagc lo beliavc generally as dominanl; sncii are epi'lermolysis 



///^//m.syy, MilUijilr TehjriiKjii-r/asis, Xailtlioinn, ////yyo///r//r;s/.s coiiiiiniilii /aiiii- 

 linrh, Mniiilil/iri.r. 



Diseases llial hrliiivc as n;cessive cliaiaclci-s are comparaliv(>ly rare in nian ; 

 alkaptoniiriii, (illiini^ni and rclinitis piginentosa may be menlioned. 



In sludyintf llie inlieritance of nervous diseases, llie disUnclion niusl be 

 made bclwecn tlic neuropalhic tempérament and organic disease. The former 

 would coni'crn llie inheritance of llie criniinal tendency, of liyslrria, melan- 

 cliolia, etc. Snch characLers may beliave as dominanis, as in luur lamilies 

 recorded by Dcjerine. The author gives brief records of a large number.of 

 familles in wliicli nervous diseases of an nndelermined type are inlierited. It 

 is noliceable tliat the numbers of those alTecled are much in excess of llie 

 unaffected. Turning to llie cases of definite organic disease, llie aullior clas- 

 sifies Ihem as follows. 



Ist. Diseases ^YilllOllt organic lésions; "ind : Dis(■asc^ willi organic 

 lésions. 



The iiiicslioii al once arises as to llie interprétation of the inherilanee of 

 epilepsy. According lo Echeveria, of Tir).") individuals issued froni iiiarriages of 

 epilcplies, 105 are normal, and 78 epileplic, and Ihe remainder are alfected 

 Avilh varions nervous diseases. Il appears from thèse facls llial the prédispo- 

 sition is hère inherited, and lliis idea is borne oui by Ihe Knowledge lliat 

 epilepsy is an acquired disease. 



The inheritance of Parkinson's disease has only been observed in a few 

 cases, and Ihe same remark applies lo Graves' <liscase. Tlioinscn's disease 

 appears to behave as a dominant; records of several faaiilies show llial il may 

 aiso be episodic in characler. 



The author has devoted sjiecial alt(Milion lo tlic stndy of organic nervous 

 diseases : Ileredilarij aUixia. The inheritance of this disease appears lo be very 

 irregular; Ihere are several types, and a similar lype runs in each family. 

 Many recorded cases show thaï the proportions of all'ected to unalTeclcd vary in 

 Ihe dilTerent families. 



Records of llie inherilanee of the l'ollowing diseases and of many others 

 are given : ('(iiujcni/al iii/slinjnii/x, ('(dk/cd/IciI IniplioeileiiKi, l'nuiimiital periodu: 

 parabjsh. 



The author considers llial llic lollowliig clas>ilicali(iii of ner\ous tliscases 

 may be established, fiom Ihe facls \\liicli hc has collccted : 



Ist: diseases wliich are inherited according lo niendelian proportions : 

 Heredttarij Churea, L'oiujenilalhyperlropldc neuritis ([ypo Pierre Marie). 



Jlereditary cerebellar alaxia (type Pierre Marie). 



Probably Ihe l'ollowing may also be included in this calegory : licliniliK 

 piymenlusd, Congenitul nystaymus. Congénital perindic paralysis, Tmphœdaiiia. 



!2nd : Diseases that do not appear to be inherited according lo mendelian 

 proportions : Tliomsens' diseagi', Frh'drc'ivli'fi disease. Mi/dlrnp/n/ ('/i/ir(ol-.\Jii rie, 

 Myopathy. 



