Referate. 355 
of these papers taken together are (1) that in Birds sex-limitation is found 
in the female, while in Mammals it is in the male; and (2) that several 
new cases are described in which the coupling with sex is partial rather 
than absolute. L. Doncaster. 
Morgan, T. H. Heredity of Body Colour in Drosophila. Journ. Experim. 
Zool. 13.1.1912. p.27—46. (1 colour plate.) 
Morgan, T. H., and Cattell, E. Data for the Study of sex-linked inheritance 
in Drosophila. Journ. Experim. Zool. 13.1. 1912. p. 79-102. 
The first paper shows that the colour of the wild fly (‘“gray’’) is due 
to there factors, Black (B), Yellow (Y) and Brown (Br). Absence of B 
produces a yellow fly, absence of Y a black fly, absence of both B and Y, 
a brown. The factor B is sex-linked, but Y is not; whether Br is sex- 
linked has not yet been determined. It is pointed out that these factors 
for body-colour appear to correspond to the three factors for eye-colour 
already described, namely vermilion, pink, and orange, of which the pink 
and orange factors are sex-linked but the vermilion is not. These is however 
no organic correlation between the body-and eye-colours, for any eye- 
colour may be associated with any body-colour. Some disturbances of the 
sex-ratio occur in the crosses with these colours, such as have been de- 
scribed in connexion with certain other mutations of Drosophila, and the 
ratios of the various colours in F, show abnormalities which may perhaps 
be accounted for by gametic coupling. 
The second paper gives a very valuable account of the phenomena of 
gametic coupling in transmission by the female of characters which are 
sex-limited when transmitted by the male. Since the male transmits such 
characters to his daughters only, they must always be associated when 
transmitted by the male; but when transmitted by the female it is found 
that characters which were associated in the grandparents reappear asso- 
ciated in the grandchildren. For example, if a red-eyed, black-bodied male 
is mated with a white-eyed, yellow-bodied female, the female offspring 
produce eggs which bear almost exclusively either the factors for red eye 
and black body, or for white eye and yellow body, the converse com- 
binations red-yellow and white-black hardly occurring. It makes no diffe- 
rence wheter a ‘present’ factor is coupled with a second ‘present’ factor, or 
with an ‘absence’. It is remarkable that the closeness of the coupling varies 
greatly in different characters; the coupling in the case of colour-factors 
is very close (about 200:1), while the coupling between the factors for 
colour and for size of wing is very low (about 2:1). This is the first case 
in which gametic coupling — alrealy well-known in plants — has been worked 
out on a large scale in an animal. L. Doncaster. 
Baltzer, P. Uber die Beziehung zwischen dem Chromatin und der Entwicklung 
und Vererbungsrichtung bei Echinodermenbastarden. Arch. f. Zellforschung. 
5. S. 497—621. 5 Tafeln. 
Um die Rolle des Chromatins bei dem Vererbungsgeschehen festzustellen, 
und zwar in Verfolg der von Boveri (in seinen Dispermieversuchen) an- 
gebahnten Gedankenwege, wurde parallel mit dem (oft behandelten) Schicksal 
der Bastardzuchten von Verf. sehr sorgfältig die Geschichte der elterlichen 
Chromosomengarnituren untersucht — auch durch Zählungen, oder an deren 
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