B26 
NATURE 
[FeBRuARY 4, 1897 
derived from the storage of furs, rugs, and valuable woollen 
goods during the summer months to prevent damage by the 
larvae of clothes moths, clothes beetles, and allied insects. This 
development raised the question as to the exact or approximate 
temperature at which furs and similar goods should be kept in 
order to maintain in a state of inactivity any destructive insects 
which they might contain. The matter was referred to Dr. L. 
O. Howard, entomologist to the U.S. Department of Agri- 
culture, but he was unable to furnish the necessary information, 
or to find any facts bearing upon the subject. A series of experi- 
ments were, therefore, begun, and the results are described in the 
Proceedings of the Eighth Annual Meeting of the Association of 
Economic Entomologists, received a few days ago. The insects 
subjected to experiment were the common clothes moth, the 
black carpet beetle, the leather beetle, the dark meal-worm, and 
a cabinet beetle. The results seem to show definitely that it is 
perfectly safe to keep materials infested by any of the insects 
mentioned at a temperature of 40° to 42° F. during the summer 
months, and that the cold-storage companies, which have been 
keeping the goods at temperatures of 12° to 20°, have been 
wasting energy in producing a temperature about 20° lower than 
is required. A number of valuable papers on economic ento- 
mology will be found in the Bzdletén (No. 6 of the U.S. 
Department of Agriculture) in which Mr. Howard’s paper 
appears. 
EMBRYOLOGICAL research is now flourishing in the Uni- 
versity of Tokyo, Japan. Part 1, vol. x. of the /owrnal of the 
College of Science in that University, consists of an elaborate 
memoir, by Prof. K. Mitsukuri, on the ‘‘ Fate of the Blasto- 
pore, the Relations of the Primitive Streak, &c., in Chelonia.” 
The text is in English, and there are eleven plates containing 
uumerous figures, both of surface views of embryos and of 
sections. The memoir is appropriately dedicated to the 
memory of the late F. M. Balfour, of whom the author is one 
of the distinguished pupils. The embryos studied were those of 
three species of turtle common in Japan, those of two of them 
having been obtained in abundance with great facility at a turtle 
farm. The observations throw a great eal of light on the nature 
of the primitive streak, and on the formation of the posterior end 
of the embryo, and the general result is to confirm and elaborate 
in detail the interpretation of reptilian development in its early 
stages, which is explained in Balfour's ‘‘ Comparative Embry- 
ology.” New suggestions, however, are made concerning the 
relations between the mode of development and the evolution of 
yolk in the various classes of vertebrates. 
THE development of the renal and generative organs in 
dog-fishes is one of the most important subjects in vertebrate 
morphology, and has occupied much of the attention of several 
eminent investigators, Prof. Carl Rabl has studied the matter 
in great detail during the past few years, and in the current 
number of the A/orphologisches Jahrbuch, edited by Gegenbaur, 
gives a new description of the history of these organs in the 
embryo, and reconsiders various questions concerning their 
evolution. 
‘THE horary values of the magnetic elements at Copenhagen, 
during the years 1893-94, are given in the ‘Annales de 
VObservatoire magnétique de Copenhague,” prepared by Dr. 
Adam Paulsen, Director of the Denmark Meteorological Insti- 
tute, and just published. 
Messrs. LONGMANS, GREEN, AND Co. have published, as a 
pamphlet of twenty-four pages, the first part of ‘* Exercises in 
Practical Physiology,” dealing with elementary physiological 
chemistry. Prof. A. D. Waller, F.R.S., and Mr. W. Legge 
Symes are the authors ; and the exercises they give should be of 
great assistance in laboratories of physiological chemistry. 
NO. 1423, VOL. 55] 
A course of six short lectures and demonstrations on fish and 
fisheries, free to the public, is now going on at University 
College, Liverpool. Prof. Herdman opened the course with an 
account of the present position of our fishing industries, and the 
advantages to be gained from biological investigations. Mr. R. 
A. Dawson followed with a lecture on the need and object of 
Sea Fishery Committees, and on the different methods of fishing 
in the Lancashire Sea Fisheries District. Some methods of 
fishing, and of fish culture in other European countries, were 
described by Mr. R. L. Ascroft on Monday evening. The three 
ensuing Monday evenings in this month will be devoted to fish 
parasites, and some constituents of the food of fishes, by Mr. 
Isaac C. Thompson; the habits and life-history of crabs and 
lobsters, by Mr. Andrew Scott; and the bacteriology of fish, 
and the connection of fish with disease, by Prof. Boyce. The 
Lancashire Sea Fisheries Committee is fortunate in being able 
to arrange a course of lectures so very serviceable to all who are 
interested in the fishing industry of the district. 
SoMEWHAT remarkable results have been obtained by Messrs. 
T. Paul and B. Kronig in an investigation into the behaviour of 
bacteria towards chemical reagents, which appears in the 
December number of the Zedtschrift fiir physikalische Chemie. 
A definite number of organisms are exposed to the action of a 
solution of the disinfectant for a definite time; after complete re- 
moval of the disinfectant, the number of organisms still capable 
of development is determined. The spores of the anthrax 
bacillus were used in the greater part of the experiments. It is 
found that the different salts of a metal possessing a specific 
poisonous character—mercury, for example—are not by any 
means equally deadly. Under otherwise similar circumstances, 
those salts which are electrolytically dissociated to the greatest 
extent are most active. For example, a solution of mercuric 
chloride contains very many more mercury ions than one of mer- 
curic cyanide of the same concentration, and the latter salt is 
very much less deadly than the former. The addition of sodium 
chloride to a solution of mercuric chloride diminishes its dis- 
infecting power to a very marked extent ; in this case, also, the 
number of mercury ions is diminished by the presence of the 
salt. This is of practical importance, because the addition of 
salt to mercuric chloride solutions is often recommended in 
order to increase its solubility. Similar results are obtained 
with silver salts ; such salts as the nitrate, chlorate, and benzene 
sulphonate, which are dissociated into their ions to a consider- 
able and approximately equal extent in aqueous solution, have 
nearly the same disinfecting action, while the addition of sodium 
thiosulphate or of potassium cyanide, with which the silver ions 
combine to form complex ions, practically destroys the disin- 
fecting action altogether. The disinfecting power of solutions 
of bases or of acids depends, on the whole, on the strength of 
the base or acid—that is, on its degree of electrolytic dissocia- 
tion. Although in all these cases the influence of the dissocia- 
tion is plainly apparent, the specific action of the anion andi of 
the undissociated molecule is by no means to be neglected. 
Hydrofluoric acid, for example, though a comparatively weak 
acid, has a more powerful action than acids like nitric or 
hydrochloric. Of practical interest is the fact that silver nitrate 
has a maximum disinfecting power when dissolved in 50 per 
cent. alcohol, while with mercuric chloride the maximum 
occurs at 25 per cent. Solutions of these salts in absolute 
alcohol are practically without effect on anthrax spores, 
THE additions to the Zoological Society’s Gardens during the 
past week include a Bonnet Monkey (Jacacus sénzcus, 9 ) from 
India, presented by Miss E. Blanche Joyce ; a White-backed 
Piping-Crow (Gymnorhina leuconota) from Australia, presented 
by Mr. H. Brame; a Kinkajou (Cercofeples caudivolvulus) from 
South America, deposited ; a Black Lemur (Lemur macaco, 2 ) 
from Madagascar, purchased. 
