The Journal of experimental zoology . can be no doubt thatwhen only one chromosome-nucleolus is present it is to be consideredas a bivalent body arising by the fusion or synapsis of the twoidiochromosomes. Thus far the facts confirm the interpretation given by Mont-gomery (oi, i) who observed in Coenus, Euschistus tristigmusand some other forms that the cells of the growth-period may showeither a single chromatin-nucleolus or (in Euschistus appar-ently more frequently) two such bodies that are unequal in size;and this fact he interpreted to mean that the two corresponding Studies on Chromosome
The Journal of experimental zoology . can be no doubt thatwhen only one chromosome-nucleolus is present it is to be consideredas a bivalent body arising by the fusion or synapsis of the twoidiochromosomes. Thus far the facts confirm the interpretation given by Mont-gomery (oi, i) who observed in Coenus, Euschistus tristigmusand some other forms that the cells of the growth-period may showeither a single chromatin-nucleolus or (in Euschistus appar-ently more frequently) two such bodies that are unequal in size;and this fact he interpreted to mean that the two corresponding Studies on Chromosomes. 393 spermatogonia! chromatin-nucleoli may either conjugate at theperiod of general synapsis to form a bivalent body or may remainseparate as univalent bodies. As already pointed out, it wasprobably this interpretation that led him to conclude that thefirst division in these forms might show either seven or eightchromosomes. But the later stages observed in Brochymenagive conclusive evidence that even though such a primary synapsis. •* ::-, 111 # • • •
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Keywords: ., bookauthorwi, bookcentury1900, bookdecade1900, booksubjectzoology
