68 
EDMUND B. WILSON 
nucleoli — are visible in the same section are not very common. 
Two such cases are shown in figs. Ik, I., each of which shows also 
four of the nine larger bivalents. 
I have not endeavored to make an exhaustive study of the 
growth-period as a whole, but the facts reported above taken in 
such a body is not present in the oocyte-nucleus, therefore the odd or accessory 
chromosome of the male cannot be derived in fertilization from the egg-nucleus 
— an obvious non sequitur. Buchner's argument, based upon precisely opposite 
data, shows a somewhat similar, though less obvious entanglement. The essence 
of his objection is given in the following passage, which at the outset accepts 
all the essential facts on which the conclusions of Stevens and myself were based. 
"Auf alle Falle haben wir nur eine Sorte von Eiern, denn dasser (the accessory 
chromosome) in einem Ei ausgestossen und im andern innenbehalten wird, er- 
scheint undenkbar. Die Spermatozoen haben das accessorische Chromosom zur 
Halfte. Nehmen wir an, die Eier besassen das accessorische Chromosom schon, 
so gabe es Tiere mit zwei Monosomen und solche mit einem — ein Fall der nicht 
existiert" (op. ext., p. 409, italics mine). This is, indeed, an astounding statement; 
for it was the very fact that there are individuals that have but one monosome 
or accessory chromosome (the males), and other individuals of the same 
species (the females) that have two corresponding chromosomes, upon which the 
conclusions of Stevens and myself were mainly based (!)• This is true, asGutherz 
('08) has shown, of the very form (Gryllus) of which Buchner is writing, the single 
odd chromosome (monosome) of the male, recognizable by its peculiar form and 
other characters, being represented in the female by two such chromosomes. 
This is also in agreement with the results of other recent workers on the Orthoptera 
including Wassilieff, Davis, Jordan andlMorse. I can therefore find no meaning 
in Buchner's statement unless the word ''Monosom'' be used to denote simply 
a chromosome-nucleolus, when the passage becomes at least intelligible. But 
such a restriction in the meaning of this word is not justified by its etyniology, 
by the original definition of its author (Montgomery, '06a, '066) nor by the facts; 
and it does not seem to accord even with Buchner's own usage elsewhere in the 
paper. That Buchner's statement is totally at variance with the facts when cor- 
rectly stated is shown by the following summary of my results, quoted from one 
of the papers in which Montgomery first defined the word ''monosome." "When 
there is a single monosome in the spermatogenesis (as in Protenor, Harmostes, 
Anasa and Alydus) there are two in the ovogenesis so that the ovogoni a possess 
always an even number af chromosomes" ('066, p. 145, italics mine). 
But even if we admit that the "accessory body" of the female is a chromosome — 
and not only is there no proof of this but many reasons for doubting it — what ad- 
verse bearing would the fact have upon the "theory"? None as far as I can see, 
unless this chromosome were proved to be univalent and without a synaptic mate 
Were all this true, new and unintelligible complications would arise in regard to the 
numerical relations of the diploid and haploid chromosome-groups in both sexes ; 
but it is not worth while to consider these puzzles since they lie in a region not of 
observed fact but of pure phantasy. 
