134 ROSS G. HARRISON 
May 2L Specimen preserved (fig. 126). Hand double; limb (TR) 
as a whole looks like a right, including the anterior hand {IRjM), 
which has two long digits and a distinct third. The posterior hand 
(hET) is a left, also with three digits, the first of which is truncated. 
Reduplication ulnar. 
20. Heteropleural, dorsodorsal 
Experiment H. R. E. 1. April 18, 1916. Posterior half of right 
limb bud in place of anterior left (fig. 120, 10). 
April 19. Well healed. 
April 21. Two distinct hmnps on operated side; dorsal one larger, 
ventro-anterior one quite small. 
April 26. Limb on operated side about as large as normal, but pro- 
jects laterally. 
May 1. Reduplication of hand; three digits, fan-like. 
May 8. Specimen preserved (fig. 127). Arm somewhat thicker 
than normal, projects posteriolaterally with hand flexed ventrally. 
Hand sjTiimetrical, with five digits, of which middle one (i) is defective. 
The posterior half of the hand {HOM) is a left, the anterior {HET) a 
right. 
Experiment H. R. E. 5. April 19, 1916. Dorsal half of right limb 
bud in place of dorsal left (fig. 120, 11). 
April 20. Perfectly healed. 
April 24. Operated limb bud not quite so large as normal, points 
laterally and slightly anteriorlv. 
April 29. Operated limb double (fig. 128). 
May 8. Specimen preserved (fig. 129). The dorsal (posterior) 
member (ROM) is a nearly normal left arm; first digit short; third is 
small, and fourth not visible. The ventral (anterior) member (BET) 
arises just below elbow, and likewise shows three digits, of which first 
is short; plane of mirroring is radial. 
Experiment H. R. E. 11. April 11, 1917. Anterior half of left hmb 
bud in place of posterior right (fig. 120, 9). Wound perfectly healed 
same evening. 
April 14. Operated limb bud very large and prominent, position 
normal. 
April 16. Limb bud massive, points dorsolaterally; almost perfect 
anteroposterior symmetry. 
April 2.3. Limb has now assumed normal position; first two digit a- 
tions show; a distinct l)ut small spur at elbow on radial border points 
laterally. 
May 4. Operated limb normal; spur much reduced. 
May 7. Specimen preserved. Arm normal; spur a mere nodule 
about middle of upper arm, radiodorsal border (fig. 130). 
Experiment H. R. E. 43- April 5, 1918. Anterior half of left limb 
bud in place of posterior right (fig. 120, 9). 
ApriJ 6. Perfectly healed. 
