100 YEARS AGO

As nest-building fishes are comparatively few, naturalists will read with interest an account given in the August issue of the American Naturalist , by Messrs. Young and Cole, of the manner in which the brook-lamprey (Lampetra wilderi) makes a structure of this nature. It is believed that the males precede the females at spawning time and commence nest-building before the arrival of the latter. The nest is made among pebbles, but it does not seem that the lampreys follow any definite plan in its construction. They affix themselves to such pebbles as require removing from the nest, and then endeavour to swim straight away with them. In the case of a heavy stone two lampreys may join forces. The number of fish in a nest may vary from one to thirty or forty; but there are generally between three and twenty-five.

From Nature 20 September 1900.

50 YEARS AGO

A sample of blood sent to us because of the presence of most unusual antibodies has proved, on investigation, to have even more extraordinary Rh antigens. The blood is unique in our experience, and in the literature, in that it has the antigen D, but lacks any detectable representative of the C and E allelomorphic series of antigens. The donor of the blood is homozygous for this deficiency, owing without a doubt to her parents being second half cousins. Her mother is heterozygous for the condition; her father and two brothers are dead. The genotype of the donor may be written —D—/—D—, the dashes representing the absence of C, c, Cw, cv, Cu and the absence of E, e, Eu. The absence of these antigens was demonstrated in negative results of agglutination tests in saline and in albumin, of indirect anti-globulin tests, of trypsin tests and of absorption tests. … In the serum of the donor we have so far been able to identify anti-e, anti-C and anti-c. The finding of both anti-C and anti-c in one serum is extraordinary but not altogether unexpected. … Whatever the exact genetic mechanism, the fact that C and E are involved supports from an unexpected angle Fisher's tentative suggestion that the order of the genes on the chromosome would be found to be D C E. It also seems that the very controversial question of whether the genes are separable or not is settled in the most convincing way of all — by their separation.

From Nature 23 September 1950.