438 ROSS G. HARRISON 
in the first digit. In one (Rem. E. 29), where the posterior half 
of the bud had been extirpated, the first digit is a mere stump 
and is syndactylous with the second, which, however, has a 
small reduplicating branch on the ulnar side (fig. 18); in the 
other (Rem. E. 21), from which the central portion had been ex- 
cised, the first digit is short (fig. 19). 
The cases with ordinary (not cleaned) wounds (Table 6), like 
the foregoing, show the highest proportion of defects after re- 
moval of the dorsal half of the limb bud. However, the lowest 
proportion of defectives occurred after removal of the anterior 
half, a result for which there is no apparent explanation. Re- 
moval of the dorsal portion gives a relatively large number of 
cases of complete suppression of the limb. Of the partial de- 
fects, the most marked case (H. E. 21—) has the hand totally 
lacking, the arm ending as a rounded stump (fig. 20); here the 
anterior portion had been removed. Another case (H. E. 13-, 
posterior half removed) appears similar though less clear. In 
four of the remaining, two of which followed extirpation of the 
posterior (Rem. E. 2 and 7), one of the ventral (Rem. E. 1) and 
one of the central (Rm. E. 9) portion of the bud, the defect in- 
volves only the first digit, which is either absent or short (figs. 21 
B-24 B), while the other two cases (H. E. 18-, removal of dorsal 
half, and H. R. E. 33-, removal of posterior half) have the second 
digit short (figs. 25 B and 26). One of the cases (Rem. E. 9) 
shows the same defect on both the operated and the unoperated 
sides (figs. 24 A and B). In a few of the cases, webbing of the 
first two fingers occurred (figs. 27 B and 28). This has at times 
been found in other experiments and even in unoperated limbs, 
and since the deviation is slight these cases have been classed 
among the normal. 
Turning to the reduplications, we find them concentrated 
among the cases in which the anterior half of the limb bud had 
been removed, six out of the eight falling within this group. 
They include a variety of forms, such as two separate and nearly 
complete limbs (fig. 34), a single normal limb with a spur at- 
tached to the upper arm (fig. 33), and a single limb with merely 
a branched or double digit (fig. 35). Three of them (Rem. E. 
