THE LIMITS OF HEREDITARY CONTROL IN 
ARMADILLO. QUADRUPLETS: A STUDY 
OF BLASTOGENIC VARIATION 
H. H. NEWMAN anv J. THOMAS PATTERSON 
From the Zoological Laboratory, University of Texas (No. 108) 
FIVE TEXT FIGURES AND EIGHT PLATES 
CONTENTS 
MORO CtI ON: ~, {cha cckie wees Pace Cecio es oc eee ate eee eee 855 
Morphology ‘of the imtegumentyedcc: 4c. se oles eee he ote ete cree ere ee 861 
Meristic variation of the elements of the nine bands of armor............... 865 
A Variation in the banded region asa whole.........:...-.---.--9--5- 865 
B Comparative variability of males and females...................... 868 
CP Variationeimolnesin Givi elvis ciind Sys ete rere sree rere 870 
D_ Fraternal correlation in the banded region as a whole; an index of the 
limits‘of hereditanyaconmtrolyer sac. cre ats sons aa noe aie: 873 
E Fraternal correlation in the individual bands.....................- 880 
Atypical variation in the individual elements and in the bands.............. 883 
A Scute ‘abnormalities’ in the species; their distribution and frequency. 883 
B Hereditary control in connection with scute ‘abnormalities’......... 888 
C Band ‘abnormalities’ in the species; their distribution and frequency. 893 
D_ Hereditary control in connection with band ‘abnormalities’ .......... 897 
Pairing, an intra-fraternal correlation; and its bearing on the problem of 
mnereditary COMUROl: stpvay se miaelsceheree chee electra sts Cie sine Aeon aie ce ee eee oe eee 905 
Maesheredubary7combrolwot/Se xan. entenes acl cte sete cine ora seus eal Siete esters ea es 910 
General Considerations eri by Gr ce sileya ech iets eee 911 
SSUMIDINT RIYA. Sc rae eg a olen frac reNsconena tote eae oy ial tne ee ee eee lca ae 914 
BH HORFAPINY issn ee eee re FE a EE Oe SE aC ee aR ae 917 
INTRODUCTION 
To what extent or within what limits are the definitive characters 
of the individual determined at the time of fertilization and in how 
far are the minutiae of organic structure to be considered as the 
product of individual variability beyond the limits of hereditary 
control? No more fundamental question could well be raised, 
and none more difficult of solution. The question has recurred 
JOURNAL OF MORPHOLOGY, VOL. 22, No. 4 
DECEMBER, 1911 
855 
