INDEX 



127 



Xasturtium officinale, 92 

 Nematoda, 42 

 Nuclear membrane, 1 



sap, 1 

 Nucleolus, 1 

 Nucleus, shape of, 2 

 Nyssia zonaria, 17 



Oecanthus longicauda, 17 

 Oenothera, G6 

 Oligochaeta, 94 

 Opalinidae, 5 

 Opisthogoneata, 42 



Pachytene, 2 -strand, 54 



4-strand, 55 

 Pairmg, at zygotene, 51 



somatic, 34 



in complex heterozygotes, 

 85 



in salivary gland chromo- 

 somes, 35 



between X- and Y-ehromo- 

 somes, 80 



segment, 80 

 Perla marginnta, 41 

 Phleum, 92 

 Photinus, 79 



Phytophaya destructor, 11 

 Pisum, 88 

 Podisma, 96 

 Polyploidy, 29 

 Polyploids, meiosis in, 82 

 Polysf)my, 45 

 Popuhts, 42 

 Prochromosomes, 4 

 Prometaphase, of mitosis, 13 



of first meiotio division, 

 62 

 Prophase, of mitosis, 8 



of first meiotic division, 49 

 Protenor, 79 

 Protozoa, 7, 13, 30 

 Pteridophytes, 47 

 Pulmonata, 94 

 Pycnosis, 6 



Raddish, 92 



Raphanobrassica, 92 



Rat, sex-chromosomes in, 79, 



Rhoeo discolor, 93 



Rhynchota, 80 



Ring- chromosomes, 32 



Rotation of chiasmata, 59 



Rotifera, 42 



Rumex, 45, 46 



Rumex acetosa, 41 



Rye, 92 



Salamandra, 16 

 Salivary Gland Chromo- 

 somes, 

 Saturnia pavonia, 74 



pyri, 74 

 Scale insects, 13 

 Scaphanorhynchus owstoni, 99 

 Schistocerca, 79 

 Sciara coprophila, 15, 76 

 Selective fertilization, 44 

 Sex-chromosomes, at mitosis, 

 39 



— at meiosis, 78 

 Spartina torvrisendi, 92 

 Spindle, 13 



attachment, 17 



elements, 13 



fibres, 19 

 Spiral structure of chromo- 

 somes, 21, 63 

 Spireme, 9 

 Stem body, 24 

 Stp.nobothras, 69 

 Synchronous mitosis, 5 



Telophase, 24 

 Terminalization, 59 

 Thysanoptera, 42 

 Trade scantia, 25 

 Trichoptera, 42 

 Trisomy, 45 

 Trivalents, 81 



Univalents, behaviour of, 75 



Quadrivalent, 82 



Vicia faba, 56 



