58 A SWEDISH FARMER'S LINEAGE 



point. One can compare the Swedish race with a lofty and vigorous fir. The 

 farmers may be discribed as the »heart» of the tree itself. 



By reason of this fact, we should give this type of family our special atten« 

 tion. Moreover, we have here a very accessible field of labour. 



A scientific investigator would, without doubt, naturally be interested in any 

 human family whatever, of high or low social standard. Farmers, peasants and 

 labourers, should interest us, quite as much as noblemen or princes. 



It is not rank, titles or, brilliant careers which are the subject of our studies 

 in race^hygiene, but it is a question, of larger or smaller groups of human beings 

 connected by blood, or race. It may easily happen, that a single poor, and de» 

 generated family can teach us more than a dozen others of average type. 



The goal, which we are striving to reach is to acquire a thorough know* 

 ledge of the laws of inheritance as appertaining to mankind. In the struggle, 

 which is before us, we must undertake assaults from as many different positions 

 as possible. 



THE SWEDISH LISTER FAMILY. 



The reason why just this family of farmers, who have lived a very long 

 time in Listerland in the south west of Blekinge, is the subject of such thorough 

 investigations, is that a very uncommon family disease obtains amongst its mem« 

 bers. This disease is known in medicinal literature, as myoklonus epilepsy. It 

 appears occasionally in other parts of the world, but nowhere is it so prevalent 

 as in the Blekinge family in question. 



It has not been observed in other parts of Sweden. In Norway it is 

 unknown. 



When I, at the end of 1890 arrived in Listerland, my first task was to in* 

 vestigate the nature of the disease. The doctors in the district had no clear idea 

 regarding the same. I had, therefore to begin from the beginning, and had to 

 note all cases of illness, from which, I worked out a genealogical table. A 

 talented school-teacher, who was a member of the family in question, and his 

 nearest relatives, were very helpful to me. I am very grateful for the admirable 

 assistance they gave me during my investigations. 



With the help of the parochial register I succeeded, after much labour, to 

 obtain such complete genealogical tables that I could trace the origin of the 

 various branches. It appeared that all lines, as it were, met at one point, that 

 is to say, all persons who were attacked by myoklonus epilepsy, 17 altogether, 

 belonging to 10 different households, were offsprings of the same ancestors, who 

 lived in the 18th century. In other families in the same district not a single 

 case of this peculiar disease was met with. Hereby I had shewn it to be highly 

 probable that the disease was hereditary, and not originating from any local con* 

 ditions, in other words not, of endemic type. 



My next task was to investigate which was the course taken by the inherited 

 disease. By careful analysis (see original work) it is demonstrated that the 

 disease is inherited as a recessive and monohybrid (simplex) factor in accordance 

 with Mendel's law. I shall revert to this question further on. 



I now began to eagerly study the disease itself, its nature and development. 



