388 JAMES CRAWFORD WATT 



assumed that the deformity was already estabhshed at the time 

 when chondrification began and its origin is thus carried back to 

 at least the fifth week and to a time when the mother would just 

 begin to suspect that she had become pregnant, as her expected 

 menstrual period would then be a week overdue. No visits to the 

 zoo were yet thought of, as this was in midwinter, and yet the de- 

 formity was even then an accomplished fact which future develop- 

 ment could not alter, but only make more clear and accentuated. 



The deformed limbs will now be described in more details 

 In each arm (figs. 3 and 4) the shoulder and scapular regions 

 appear normal, but slightly flattened, as though from pressure 

 from the body lying on its side. The upper arm segment lies 

 parallel to the long axis of the body, close in at the side, and 

 appears flattened from side to side so that its mediolateral trans- 

 verse diameter is only two-thirds that of the dorso ventral. It is 

 gently tapering in outline, narrowing as the elbow is approached. 

 The elbow is fairly well rounded, and from it the forearm runs 

 forward in the same plane as the upper arm and flexed on it at an 

 acute angle, being maintained in the position by a thick web of 

 skin extending across the interval between arm and forearm. The 

 part of the forearm beyond the attachment of the web is rounded, 

 with its transverse diameters about equal, and tapers gradually 

 distally. The carpus, metacarpus and the single digit also taper 

 continuously distally, and are all in a position of partial flexion, 

 showing marked creases or folds on the volar surface at the line 

 of the joints. There is a well developed nail on the digit, but 

 it does not yet reach to or project beyond the end of the finger, 

 as is the case in a child born at full term. 



The left forearm and hand (fig. 3) are in the same plane as the 

 upper arm and in a position of complete pronation. The hand 

 lies against the side of the cheek, the palm facing directly ven- 

 trally. Flexion in this hand is gradual. 



The right forearm and hand (fig. 4) are in a position midway 

 between pronation and supination, a position identical with that 

 normally assumed when the limb skeleton is first defined (Lewis, 

 Keibel and Mall's Human Embryology). The distal end of the 



