594 



SCIENCE 



[N. S. Vol. XXVI. No. 670 



largely true, because I believe that attention 

 is genetically and chiefly a product of vision, 

 and that vision of the older and simpler type 

 of eye and mind was indeed that of a con- 

 tinuous linear stream of single images 

 (objects) focused one after another at the 

 macula. But the modern mind (of the great 

 and rapid reader, of the musician, and of 

 men in many trades and callings) is learn- 

 ing to see and know and use many synchronous 

 and coordinated images, and streams of 

 images, both at and away from the macula. 

 There is a growth and extension of the mac- 

 ular region and of its imaging, one may say, 

 or the power of attention and consciousness 

 is growing more and more able to receive, in- 

 terpret and control the many streams (which 

 is the same thing as the enlarged stream of 

 sand grains), of images focused in and about 

 the macula. Thus mental largeness, power, 

 attention and consciousness are growing at 

 a gTeat rate in our complex and difFerentiating 

 civilization, and the old nomenclature based 

 upon the hour-glass comparison is no longer 

 adequate. Especially- if is added the marvel- 

 ous power of the ear, as in the musician, to 

 receive, encompass and be conscious of ten, 

 fifty or even a hundred streams of discrete 

 synchronous tones. The following terms may 

 therefore be found useful: 



Bight-handed. — ^Preferring the dextral hand 

 for the more expert or intellectual tasks. 

 Whence right-handedness. 



Left-handed. — ^Preferring the sinistral hand 

 for the same tasks. Whence left-handedness. 



Right-eyed. — Preferring the dextral eye as 

 the dominant one. 



Left-eyed. — Preferring the sinistral eye as 

 the dominant one. 



Bighi^pared. — Preferring the dextral ear as 

 the one with which to hear sounds. 



Left-eared. — Preferring the sinistral ear 

 with which to hear. 



Bight-footed. — Choosing the dextral foot as 

 the one to guide and base action, from which 

 to spring in beginning to march, in spading, 

 etc. " Step off with the left foot forward." 



Left-footed. — The power is furnished and 

 governed by the sinistral foot. 



Bight. — Moral, good, etc. 



Sinister. — Unlucky, gloomy, etc. 



Dexterity. — Expertness, agility, etc. 



Dextrous. — Expert, agile, etc. 



Because of popular usage, the four preceding 

 may retain their vague significance in com- 

 mon speech, but not in science. 



Dextral. — Pertaining to the organs on the 

 right side of the body, regardless of expert- 

 ness, preference, etc. When facing east the 

 dextral hand is on the south side, the sinistral 

 on the north side. 



Sinistral. — Pertaining to the organs on the 

 left side of the body, regardless of special 

 preference, expertness, etc. 



Dextrality, Sinistrality. — The correspond- 

 ing abstract qualities, regardless of expert- 

 ness, etc. 

 , Dextrad, Sinistrad. — Toward the dextral or 

 sinistral side of the body, respectively. 



Dextromanual, Sinistromanual. — ^Pertaining, 

 respectively, to the dextral or to the sinistral 

 hand without regard to expertness, etc. 



Dextrocular, Sinistrocular. — Pertaining to 

 the eye on the dextral side, or the sinistral 

 side, respectively, regardless of expertness, etc. 



Dextropedal, Sinistropedal. — Pertaining to 

 the feet, in the same way. 



Dextraural, Sinistraural.—'PeTtaiamg to the 

 ears, in the same way. 



Dextrocerelral, Sinistrocerehral. — Located 

 in the right, or the left, cerebral hemisphere, 

 respectively. 



Ambidextral, Ambidexterity. — Words with- 

 out sig-nificance, or existence in fact, " ghost- 

 words," which should never be used. 



Dominant Eye.. — The eye which is uncon- 

 sciously and preferentially chosen to guide de- 

 cision and action. 



Divided Dominance, or Equidominant Eyes. 

 ■ — With shared or equal dominance. 



Alternating Dominance of the Eyes. — Domi- 

 nance of one eye at one time or for one func- 

 tion, alternating with that of the fellow for 

 another time or function. 



Beversed Dominance. — The left, because of 

 ametropia, disease, operation, etc., of the right, 

 becoming the dominant eye in the right- 

 handed; or vice versa in the case of the left- 

 handed. 



Dextroexpertness. — Conjoint and superior 



