Marcu 19; 1914] 
NATURE 63 
but if this be the case, two years seems a too 
generous allowance of time to be occupied in 
passage through the press, to the exclusion of 
belated additions, even in the case of an elaborate 
monograph such as that under review. The 
volume of text concludes with a full and well- 
planned index, while there is the useful luxury of 
a second index at the end of the vclume of plates. 
Special praise must be accorded to the plates, 
upwards of 100 in number, which illustrate this 
work. These are well reproduced in collotype 
process from beautifully executed drawings, 
mainly by Miss Frances Wieser, of the United 
States Geological Survey. The careful and de- 
tailed work of the artist is a fine achievement. 
To many who have little acquaintance with 
the Cambrian brachiopods beyond the scanty 
assemblage found in our own country, the perusal 
of this volume of plates will prove a revelation. 
It is indeed astonishing to find that such a pro- 
fusion of species had been evolved and_ such 
elaborate specialisation had been attained by many 
of them in those remote ages. One can only 
picture in imagination the long and slowly evolv- 
ing lines of precursors of which no trace has yet 
been found. 
Dr. Walcott deserves the warmest thanks of 
all paleontologists and geologists for a treatise 
which must long remain a classic. The public 
department which has issued the work in such 
handsome form is also to be congratulated. What 
higher service can such a department perform 
than thus to give practical encouragement to 
arduous scientific labour ? ets) KX. 
THE TRANSMISSION OF PLAGUE: BY 
FLEAS. 
(ae third Plague Supplement of the Journal 
of Hygiene maintains the high standard both 
of research and of editing set by the previous 
numbers. It contains eight good articles, chiefly 
by S. Rowland and R. St. John Brooks, on the 
bacteriology of plague and by A. W. Bacot on the 
rat flea. ‘he former articles deal with the in- 
fluence of cultivation in serum-containing media 
upon the virulence and immunising properties of 
the plague bacillus; upon the facility with which 
it is ingested by human leucocytes; and upon its 
virulence—all points of importance in regard to 
bacteriology in general. Mr. Bacot’s most labori- 
ous and well-set-out researches upon the influence 
of temperature and humidity upon the pathophores 
and on the effect of vapours as insecticides deserve 
much commendation; but perhaps the most inter- 
esting article is by him and Prof. C. J. Martin on 
the mechanism and transmission of plague by fleas. 
They sum up a very careful paper by the following 
remarks :— 
‘‘Under conditions precluding the possibility of in- 
fection by dejecta it was found that two species of 
rat fleas, Xenopsylla cheopis and Ceratophyllus 
fasciatus, fed upon septicaemic blood, can transmit 
plague during the act of sucking, and that certain 
individuals suffering from a temporary obstruction at 
the entrance to the stomach were responsible for most 
NOM2a16,, VOL. 93)| 
of the infections obtained, and probably for all. In 
a proportion of infected fleas the development of the 
bacilli was found to take place to such an extent as to 
occlude the alimentary canal at the entrance to the 
stomach. The culture of pest appears to start in the 
intercellular recesses of the proventriculus, and grows 
so abundantly as to choke this organ and extend into 
the cesophagus. Fleas in this condition are not pre- 
vented from sucking blood as the pump is in the 
pharynx, but they only succeed in distending an 
already contaminated oesophagus, and, on the cessa- 
tion of the pumping act, some of the blood is forced 
back into the wound. Such fleas are persistent in 
their endeavours to feed, and this renders them par- 
ticularly dangerous.” RR: 
NOTES. 
WE announce with deep regret the death on March 
16, as the result of a motor accident, of Sir John 
Murray, K.C.B., F.R.S., the distinguished naturalist 
and oceanographer. 
THe Right Hon. Sir Francis Hopwood has been 
appointed by the president and council of the Royal 
Society to a seat on the general board and executive 
committee of the National Physical Laboratory, in 
succession to Sir Arthur Rticker, F.R.S., resigned. 
WE notice with regret a Reuter message from New 
York reporting the death on March 16 of Prof. E. S. 
Holden, director of the Lick Observatory from 1888 
to 1898, and author of a number of papers and other 
works on astronomical subjects. 
Tue death is announced, on March 7, at seventy- 
three years of age, of Prof. Antonino Salinas, pro- 
fessor of archeology at the University of Palermo 
and director of the Archeological Museum. 
Pror. J. G. Apami, F.R.S., Strathcona professor 
of pathology and bacteriology, McGill University, 
Montreal, has been awarded the Fothergill gold medal 
of the Medical Society of London for 1914, for his 
work on pathology and its application to practical 
medicine and surgery. 
Tue death is announced, in his sixty-seventh year, 
of Dr. E. J. Houston, one of the inventors of the 
Thomson-Houston system of are lighting. He was 
twice elected president of the American Institute of 
Electrical Engineers, and was the author of more 
than fifty books, mainly on electricity and allied sub- 
jects. 
Pror. F. Keresie, F.R.S., professor of botany, 
University College, Reading, has been appointed 
director of the Royal Horticultural Society’s garden at 
Wisley, with the view of making it of more general 
practical service. Mr. F. Chittenden will remain in 
charge of the educational section, and Mr. S. T. 
Wright will continue to act as superintendent of the 
garden. 
Miss A. Cannon, whose critical examination of 
Harvard College Observatory photographs has led her 
to the discovery of many new variable stars and other 
objects of interest, has been elected an honorary mem- 
