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the Fi»males also corroborate this. And it becomes still more probable through
being able to Seiler and Doncaster prove, that the lepidoptera, contrary to
other insects, are heterogametic in the female genus. My experiments to prove
the existence of heterochromosomes in anachoreta females, have hitherto led to
nothing, and since the summer 1917 I regret to say, that I have not succeeded
in getting the necessary material of this species, rare in Sweden and Finland.
I will only add a few lines about my purely experimental research.
A small paper in 1916 treats of the dimorphism of the Sphingid larvae, a
question much discussed by evolutionists. Through the four possible crossings
between imagines, derived from green and black larvae of Chaerocampa elpenor
it is proved, that both the forms are isogenic and thus do not possess any selec*
tional value. The species consequently possesses a factor, which under certain
circumstances has the power of producing black pigment in the skin of the larva,
under others, however, lacks this power. The said factor is inherited both if
it has been activised, as is the case with the black larva, or if it remains inactive,
as is the case with the green form. The contest about the different value of
selection of the different phaenotypes and their phylogenetic age has consequently
been a contest about the beard of the pope.
Since 1914 the author has been working at a mendelian analysis of the
lepidopterous formae Spilosoma lubricipeda, intermedia and zatima■ Zatima is a
strongly, intermedia a weaker melanistic form of lubricipeda, which is yellowish
with a small number of tiny little black spots. The melanism is produced by a
factor Z, which is homozygotic in zatima ZZ and heterozygotic in intermedia
Zz: it fails in lubricipeda zz. But this factor Z is altered in a high degree by
a number of polymere factors, which strengthen the influence of Z. If the poly»
mere factors are all homozygotic, a ZZ»individual becomes nearly uniformly black,
however if they are absent, a zatima may become nearly white with just a few
black spots. On the Zz*individuals the influence of the polymere factors is just
as strong, while the rare and small black spots in lubricipeda are changed very little.
Through the influence of the polymere factors, not yet finally analyzed, a continuous
series of phaenotypes is produced, ranging from an almost purely black specimen
to a nearly white one. It is of course theoretically possible to receive all these
different phaenotypes, which are also different biotypes, in one sole Crossing; in
faet it has been successfully performed, with the exception of the very rare most
extreme forms. A preliminary paper about this research was published in 1920.
For the sake of completeness I beg to State, that Professor Alex. Luther has
examined the heredity of Agriolimax agrestis and Agr. reticulatus and among
other things he has found, that a totally albinotic form of the latter, observed in
nature, differs from the normally pigmented one only as to one factor: further
that the manager of the zoological garden at Högholmen near Helsingfors Mag.
phil. Rolf Palmgren during the last few years has attempted a few hybridisations
between different species and races of mammals and birds and succeeded in arriv»
ing at some new and remarkable hybrids.
Further I beg to add, that papers about the significance of heredity in connec»
tion with some human diseases and anomalies, are to be found in the transac»
tions of the Society of Physicians (»Finska Läkaresällskapets Handlingar»).
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