24 
SUMMARY OF CURRENT RESEARCHES RELATING TO 
based on facts.” Neutral variations occur, and there is sometimes a. 
resemblance due to coincidence rather than to inheritance. This sounds 
like proving too much ; but we have not seen the original. 
Inheritance of Immunity.* * * § — Dr. A. Reibmayr has published an 
interesting essay on the evolution of immunity in the course of natural 
selection. Morbid conditions and tendencies are inherited, but so is 
immunity ; and in the struggle between these the all-important factor 
is that the conditions of function and environment do not abet the morbid 
inheritance. There seems some evidence that females are more impor- 
tant than males in conserving and transmitting the immunity. 
Variations and Races of the Mackerel.f — Mr. W. Garstang has 
investigated the various races and migrations of the mackerel ( Scomber 
scomber), and concludes that those which frequent British waters are not 
exactly alike in all localities, but possess certain average peculiarities 
which distinguish one local race from another, as is shown in elaborate 
detail. The peculiarities are greatest between the races of localities 
which are geographically remote, and least between those which occupy 
areas that are geographically contiguous. Between the mackerel of the 
North Sea and those of the English Channel there are no differences at 
all ; but the Irish race is distinctly divisible into two stocks, one of which 
is restricted to the west coast, the other to the south. A considerable 
amount of mixture takes place between the southern Irish stock and the 
fish which frequent the mouth of the English Channel. The western 
Irish stock represents more closely than any other race the primitive 
type of mackerel, from which all, whether British or American, have 
been derived. 
Respiration in Cyclostomes.J — E. Couvreur publishes the results 
of his study of the mechanism of respiration in young lampreys in the 
Ammocoete stage. The respiratory movements occur normally at the 
rate of about eighty a minute, but may rise to a hundred in excitement, 
or may be entirely suspended for a considerable time. During inspira- 
tion the lingual piston is projected forwards, thus opening the orifices 
to the respiratory tube (oscula) ; the walls of the body are expanded in 
the branchial regions, and the sphincters of the openings to the exterior 
are relaxed. Water then enters the branchial sacs by the oscula and 
spiracula simultaneously. During expiration the piston is retracted,, 
and water flows out only by the spiracula, which are slightly open.. 
When the lamprey is fixed, it both inspires and expires through the 
spiracles alone. Couvreur finds that the synchronism between the 
respiratory movements and the contractions of the heart recently dis- 
covered in Teleosteans obtains also in the lamprey, the projection of 
the piston corresponding to the systole, its retraction to the diastole 
of the heart. 
Retrospects — Prof. A. S. Packard, as chairman of the zoological 
section of the American Association for the Advancement of Science,. 
* ‘Die Immunisirung der Familien bei erblichen Kranklieiten,’ Leipzig und 
Wien, 1899 (published 1898), 8vo, 51 pp. 
f Journ. Mar. Biol. Ass., v. (1898) pp. 235-95. 
% Ann. Soc. Linn. Lyon, xliv. (1898) pp. 105-9 (2 figs.). 
§ Proc. Amer. Ass. Adv. Sci., xlvii. (1898) 48 pp. 
