12 TRANSACTIONS LIVERPOOL BIOLOGICAL SOCIETY. 



The impression that a difference in nutrition has something to 

 do with the matter is favoured by there being often a noticeable 

 hemi-atrophia on the weaker (right) side, and the hair on the 

 limbs and chest is sometimes rather more abundant or more 

 marked on the left than on the right. 



Among deaf-mute children we get no stammering that I am 

 aware of, but quite a number of them (about 7| per cent, in the 

 School for the Deaf and Dumb) are left-handed and spell and 

 sign with the left hand on the right instead of th^ right hand on 

 the left as is usually the case. These are all taught to write 

 with the right hand and they do this excellently, but 

 occasionally they have a peculiar type of ambidexterity, and 

 are known as mirror- writers, because they can write with the 

 left hand from right to left, and will read such writing as quickly 

 and accurately as you and I can do it in the ordinary way. 

 They are called mirror- writers because to read their left-handed 

 writing we require to hold the paper or slate before a looking 

 glass. 



These children seem to be able to see things the wrong way 

 round without being educated to do so, and they illustrate 

 another form of unusual bilateral co-ordination. [Several deaf 

 and dumb " mirror- writer " children shown to illustrate this 

 condition.] 



There are some other cases which we meet with in the 

 hospitals which throw light on the way in which normal 

 bilateral co-ordination is maintained. It is well known, for 

 instance, that when the eyes are moved from side to side, or in 

 any given direction the relationship of their axes to one another 

 remains the same, excepting in cases of general enfeeblement in 

 children, when the eyes may act to a certain extent independ- 

 ently of one another. But suppose that something happens to 

 weaken one of the ocular muscles, say the right external rectus, 

 so that when the patient is asked to look to the right there is 

 difficulty or inability to turn the eye in that direction. Ask 



