Journal of experimental zoology . t as early as the fertilized egg,but there is a wide divergence of opinion in regard to the condi-tions preexisting in the gametes prior to their union.^ The fact that in some organisms (such as Dinophilus, Hyda-tina or Phylloxera) the unfertilized eggs, sometimes even in theovary, are visibly distinguishable as male-producing and female-producing forms, has led a number of recent writers to deny thatthe spermatozoon can play any part in sex-determination. Beard,tor example, asserts that The male gamete, the spermatozoon,has and can have absolutely no influenc
Journal of experimental zoology . t as early as the fertilized egg,but there is a wide divergence of opinion in regard to the condi-tions preexisting in the gametes prior to their union.^ The fact that in some organisms (such as Dinophilus, Hyda-tina or Phylloxera) the unfertilized eggs, sometimes even in theovary, are visibly distinguishable as male-producing and female-producing forms, has led a number of recent writers to deny thatthe spermatozoon can play any part in sex-determination. Beard,tor example, asserts that The male gamete, the spermatozoon,has and can have absolutely no influence in determining the sex ^The general question of sex-determination, with its literature, has within the past five yearsbeen so ably and thoroughly reviewed by Cudnot, Strasburger, Beard, von Lenhossek, O. Schultzeand others, that I shall here limit myself in the main to an analysis of the new observations broughtforward. Studies on Chromosomes 25 OoGONiA Fertilization AND Synapsis , ?^ Spermatogonia Gametes Spermatozoa Zygotes. /// Nezcira Fig. 6. 26 Ed run lid B. Wilson of the offspring (02, p. 712); and a similar conclusion, thoughless dogmatically stated, is reached in the general reviews ofLenhossek (03) and O. Schultze (03). The opposite view thatthe spermatozoon alone is concerned m sex-determination (whichlike the preceding one, is of very ancient origin) has, however, beenmaintained by some recent writers, for instance, Block (whosework I know^ only from Cuenots review) and McClung, as alreadymentioned.^ On the other hand, both Cuenot (99) and Stras-burger (00) in their able reviews, have argued that both gametesmay be concerned in sex-determination; and the last namedauthor urged the view, afterward recognized as probable byBateson and developed in detail by Castle (03), that sex-produc-tion takes place in accordance with the Mendelian principles ofinheritance. The observations here brought forward, together with those ofStevens on Tenebrio, establish the predestinati
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