274 SUMMARY OF CURRENT RESEARCHES RELATING TO 
continues the history to Yon Baer and Louis Agassiz, and onwards. 
After re-stating his own terminology, Prof. Hyatt expresses his con- 
viction that “ the cycle of the ontogeny is the individual expression and 
abbreviation recapitulation of the cycle that occurs in the pliylogeny 
of the same stock ; and, while the embryonic, nepionic, and neanic 
stages give us, in abbreviated shape, the record of the epacme, the 
gerontic stages give, in a similar manner, the history of the paracme.” 
The author also expounds the law of acceleration in the inheritance of 
characters, or tachygenesis. It has been found that characteristics are 
inherited in successive species or forms in a given stock at earlier and 
earlier stages in the ontogeny of each member of the series. This law 
is called “ the crawling, walking, hopping, skipping, and jumping law.” 
Nocturnal Protective Coloration.* — Mr. A. E. Verrill discusses the 
nocturnal protective coloration of mammals, birds, fishes, insects, &c. 
He notes the prevalence of black, dark-brown, and grey among animals 
of nocturnal habit, and points out the great protective value of these 
colours, especially when they are' broken up by patches of white or light 
yellow, thus obscuring the outlines of the animal and giving the effect of 
patches of moonlight on a shadow. The colours of many butterflies, con- 
spicuous during the day, blend so well with the flowers on which they 
rest at night, that they are not readily distinguishable from them even 
in bright moonlight. The markings of tiger, leopard, jaguar, &c., are 
much more effective for concealment in the dusk than by day. In the 
second part of his paper, Mr. Verrill records his observations on colour- 
changes in fishes, and in the common squid during sleep. Some species 
of fishes while asleep have colours veryMifferent from those seen in the 
daytime, and very many show a marked increase in intensity or con- 
trast of colours. The scup or porgy ( Stenotomus chrysops') is silvery 
during the day, with a pearly iridescence, but at night it becomes a dull 
bronze or grey, with transverse black bands. The common squid at 
night takes on its darkest colours. It has the power of changing its 
colours at will, but its nocturnal colour is probably automatic and pro- 
tective. 
Air and Life.j — Dr. H. De Varigny has translated his essay on 
* L’Airetla Vie,’ which gained a Smithsonian prize. He deals first with 
the air from a chemical and physical point of view, and then passes to 
the biological role of the various constituents considered both chemically 
and physically. The essay combines in attractive form much useful 
information, e.g. as to anaerobic organisms, the role of micro-organisms in 
the assimilation of atmospheric nitrogen, the effects of altered pressure, 
the biological role of substances suspended in the atmosphere, and so on. 
Some Questions of Nomenclature^ — Dr. Th. Gill took this as the 
subject of his address to the Zoological Section of the American Asso- 
ciation. He discusses the history of nomenclature, the “ Draconian code ” 
provided by Linnaeus and Artedi, the misapplication of names, the varia- 
tions of names, the making of names, and so on. The latter part of the 
address considers the various ways of stating the grades of classification 
from phylum to variety. 
* Amer. Nat., xxxi. (1897) pp. 99-103. 
t Smithsonian Misc. Coll., 1071 (1896) 69 pp. 
% Proc. Amer. Ass. Adv. Sci., xlv. (1896 meeting) 1897, pp. 135-65. 
