

CONTENTS. 



PAGE. 



I. The Origin of Gynandromorphs. By T. H. MORGAN and C. R. BRIDGES ......... 1 



Frequency of Occurrence of Gynandromorphs ............................. 10 



Relative Frequency of Elimination of the Maternal and Paternal Sex 



Chromosomes .................................................. 11 



Distribution of Segmentation Nuclei as deduced from Distribution of the 



Characters of Gynandromorphs ................................. 12 



Starting as a Male vs. Starting as a Female ................................ 12 



Cytological Evidence of Chromosomal Elimination .......................... 13 



Earlier Hypotheses to explain Gynandromorphs ............................ 17 



The Origin of the Germ-cells in Flies .................................... 22 



Courtship of Gynandromorphs ........................................... 22 



Phototropism in Mosaics with one White and one Red Eye ................. 23 



Sex-limited Mosaics .................................................... 24 



Somatic Mosaics ....................................................... 26 



Somatic Mutation ...................................................... 27 



Mosaics in Plants ...................................................... 32 



Classification and description of Gynandromorphs of Drosophila ............. 33 



Gynandromorphs approximately bilateral ................................ 35 



Gynandromorphs mainly female ........................................ 41 



Gynandromorphs mainly male .......................................... 48 



Gynandromorphs roughly "fore-and-aft" ................................. 51 



Gynandromorphs produced by XXY females ............................. 53 



Gynandromorphs of complex type ....................................... 55 



Special Cases ...................................................... 57 



Gynandromorphs with incomplete data .................................. 70 



Drosophila Gynandromophs previously published ......................... 72 



Gynandromorphs and Mosaics in Bees .................................... 74 



Gynandromorphs in Lepidoptera ......................................... 81 



Other Insects ........................................ 94 



Spiders ............................................. 94 



Crustacea ........................................... 95 



Molluscs ............................................ 97 



Echinoderms ........................................ 98 



Vertebrates ......................................... 98 



Fishes .............................................. 98 



Amphibia ........................................... 99 



Reptiles ............................................ 101 



Birds ............................................... 101 



Mammals Man ..................................... 106 



Is Cancer a Somatic Mosaic? ............................................ 108 



Is the Freemartin a Gynandromorph? .................................... 109 



Summary ............................................................. Ill 



Literature Cited ...................................................... 116 



II. The Second Chromosome Group of Mutant Characters. By C. B. BRIDGES and 



T. H. MORGAN ................................................ 123 



Introduction ........................................................... 125 



Chronological list of the II Chromosome Mutations .................... 126 



Map of Chromosome II ............................................. 127 



Speck ................................................................. 128 



Olive ................................................................. 135 



Truncate .............................................................. 136 



Truncate Lethal ................................................... 138 



Snub ............................................................. 140 



Truncate Intensification by Cut ..................................... 143 



in 



