ORGANIC SYMMETRY IN ARMADILLO QUADRUPLETS. 193 



left margin of band 6, and fetus III. has a similar element 3 places 

 from the right of band 7. Note that these fetuses are not pairs 

 but face each other from opposite sides of the vesicle. Both are 

 secondary bud individuals. 



Set C 30 (p. 185). Fetuses I. and II., a pair, have striking 

 mirror-image resemblance. Fetuses III. and IV., the other pair, 

 have the same anomalous element bilaterally. 



Set C 76 (p. 184). Fetus III. has a double scute 12 places to 

 the right of the middle of band 2. Fetuses II. and IV. each have 

 identical elements on the left side. 



Set K 18 (p. 186). Fetus I. has a double scute 10 places to the 

 left of the middle of band 6. Fetus III., which faces I. across 

 the vesicle, has a similar element 10 places to the right of the 

 middle of band 6. 



D. Cases of Half -Band Reversals of Symmetry between Mother 

 and Offspring. In this group are included cases in which the 

 parent and offspring have the anomaly confined to the same, 

 right or left, half of the carapace, but the symmetry of that half 

 of one is the mirror-image of the same half of the other. 



Set K 70 (p. 185). Mother has a double scute 6 places to the 

 right of the middle of band 2. Fetus I. has a double scute 6 

 places from the right hand margin of band I. If this band had 

 been arranged so that the right hand half were simply shifted 

 over to the left side it would have been an ordinary case of 

 mirror-imaging. 



Set K 25 (p. 185). Mother has a double scute 6 places to the 

 right of the middle of band 2. Fetus I. has a similar element 7 

 places from the left hand margin of band I . This is a case of a 

 double reversal. Turn either of these half bands end for end and 

 an ordinary mirror-image case would result. 



Set C 4 (p. 1 86). Mother has a double scute 5 places from the 

 right margin of band 7. Fetus II. has a similar element 5 places 

 to the left of the middle of band 3, which is evidently the reversed 

 mirror-image of a similar element in band 7 of the same fetus 

 situated 8 places from the right-hand margin. 



E. Cases of Half -Band Reversals between Different Fetuses of a 

 Set. These are cases strikingly like the unilateral reversals of 

 finger-print patterns described by Wilder for duplicate human 

 twins. 



