this is the result of two combined unfavorable effects of the culture conditions : the lack of simultaneous volumetric growth of the foot- or handplate , which normally would provide the necessary space for the laying down of a pentadactylous pattern , and a loss of cells resulting from abnormal cell death affecting selective mesodermal sites in the zeugopod and in the marginal subridge area , the latter being more severely affected in hindlimb buds .
C0016504
foot
C0023216
hindlimb