n8 



Heredity and Environment 



MENDELIAN INHERITANCE IN MAN (Continued) 



TERATOLOGICAL AND PATHOLOGICAL CHARACTERS 



Dominant 

 Nervous System: 

 Normal 



Normal 



Normal 



Normal 

 Normal 



Huntington's Chorea 

 Muscular Atrophy 

 Eyes; 



Hereditary Cataract 

 Pigmentary Degeneration of 



Retina 

 Glaucoma (Internal pressure 



and swelling of eyeball) 

 Coloboma (Open suture in 



iris) 



Displaced Lens 

 Ears; 

 Normal 

 Normal 



Recessive 



Multiple Sclerosis (Diffuse de- 

 generation of nerve tissue) 



Friedrich's Disease (Degenera- 

 tion of upper part of spinal 

 cord) 



Meniere's Disease (Dizziness 

 and roaring in ears) 



Chorea (St. Vitus Dance) 



Thomsen's Disease (Lack of 

 muscular tone) 



Normal 



Normal 



Normal 

 Normal 



Normal 

 Normal 

 Normal 



Deaf-mutism 



Otosclerosis (Rigidity of tym- 

 panum, etc., with hardness of 

 hearing) 



SEX-LINKED CHARACTERS* 



Recessive characters, appearing in male when simplex, in female when 

 duplex. 



Normal Gower's Muscular Atrophy 



Normal Haemophilia (Slow clotting of 



blood) 



Normal Color Blindness (Daltonism; in- 



ability to distinguish red from 

 green) 



Normal Night Blindness (Inability to see 



by faint light) 



Normal Neuritis Optica (Progressive 



atrophy of optic nerve) 



* See page 180. 



