FEBRUARY I, 1917] 
3500 square miles, I have so far received 250 records 
in which the time is given, from the outer sound-area 
of about 5700 square) miles 223 records (including 
122 from Norfolk and fifty-six from Lincolnshire), 
and from the zone of: silence of about 4500 square 
mifes only one, and that one close to the sea. The 
greatest distance to which the sound-waves penetrated 
is about 121 miles. 
A remarkable feature about these records is that, 
though all of them have been sent in reply to my 
newspaper letters (and therefore sent as it were at 
random), they are almost as thickly grouped near the 
boundaries as near the centres of the two areas. 
There is none of that increasing sparseness of records 
near the boundary which is so characteristic of earth- 
quake investigations. It would seem as if the 
boundary were determined, not by the sound-vibra- 
tions becoming inaudibie, but by the absence of sound- 
vibrations from the area beyond. It may be of interest 
to add that, at a large number of places, pheasants 
showed signs of alarm, as they did during the North 
Sea battle of January 24, 1915. 
May I, in conclusion, state how glad I should be 
to receive (address: 16 Manor Road, Edgbaston, 
Birmingham) further accounts of the explosion, and 
especially negative records? Observations on the 
direction of the surface and upper winds would be. of 
great value. Cuartes Davison. 
RECENT PAPERS ON PARASITES. 
O*E of the most notorious of protozoan parasites 
at the present time is the microsporidian Nosema 
apis, which, since the well-known researches of Drs. 
H. B. Fantham and Annie Porter in 1912, has been 
generally regarded as the cause of ‘Isle of Wight 
disease’ in hive-bees. In the Proceedings of the 
Royal Physical Society of Edinburgh (vol. xx., part 1) 
two papers have lately appeared in which this conclu- 
sion is called in question—one by John Anderson, 
the other by the same author in collaboration with 
Dr. John Rennie. Stress is laid on the possibility of 
bees heavily infested with Nosema showing no 
symptoms of the disease; this condition was recog- 
nised by Fantham and Porter, who attributed it to 
immunity in certain strains, and directed attention to 
the danger caused to other bees by such ‘‘carriers.” 
On the other hand, an epidemic of disease among 
bees on Deeside with all the characteristic ‘‘Isle of 
Wight’’ symptoms appeared to be unaccompanied 
by any trace of Nosema in the affected insects. It 
may, of course, be retorted that the parasites were 
present in inconspicuous stages and in relatively small 
numbers, as Fantham and Porter concluded to be the 
case in similar instances observed by them. Anderson 
and Rennie, however, ‘‘are unable to recognise any 
causal relation between the presence of this parasite 
and the disease,’ though it ‘‘may be a contributing 
weakening factor favouring in certain cases the de- 
velopment of the disease.”” It may be doubted if the 
authors sufficiently recognise the possibly deadly 
effects, on certain strains of bees, of parasites so few 
in number as to escape observation. 
Students of the Sporozoa will read with more than 
usual interest Dr. Howard Crawley’s paper entitled 
“The Sexual Evolution of Sarcocystis muris” (Proc. 
Acad. Nat. Sci., Philadelphia, Ixviii., part 1), in 
which the early development of the parasites in the 
intestinal cells of the mouse is described with numer- 
ous figures.. The spores swallowed by the mouse reach 
the hinder-end of the smali intestine within an hour 
and invade the epithelial cells. Some spores then 
undergo a great enlargement of the nucleus and de- 
generation of the cytoplasm, while others remain much 
as when they entered. the cell, becoming, however, 
NO. 2466, VOL. 98] 
NATURE 
439 
relatively. shorter and broader than the original spores ; 
the author regards the former as male and the latter 
as female gametes. From six to fifteen hours after 
penetration chromatin granules separate from the 
nucleus and are absorbed by the protoplasm; this 
process is interpreted as maturation. ‘Finally, in the 
eighteen-hour stage, macrogametes may be found 
which in some cases show minute, thread-like bodies. 
upon their surfaces, and in others contain within their 
substances small, solid chromatic bodies, one in each 
case. These appearances are regarded as warranting 
the interpretation that fertilisation talses place.’ Dr. 
Crawley’s work goes far to establish the existence of 
a sexual phase in the sarcosporidian life-cycle, but it 
appears to fall short of demonstration, 
In the Proceedings of the U.S. National Museum 
(vol. 1., No, 2131) an important systematic paper on 
‘* Nematode Parasites of the Rodentia and Hyracoidea ’* 
has been published by Maurice C. Hall. Most of the 
species described are illustrated by clear structural 
figures, and there are diagnoses of the various classifi- 
catory groups, so that the paper will be of much value 
to students. In the class-diagnosis of the Nematoda 
it is rather surprising to find no stress laid on the 
entirely epithelial nature of the intestinal wall or on 
the anomalous character of the body-cavity. 
Several papers on parasites are to be found in the 
lately issued third and fourth reports of the director 
of veterinary research for the South African Union 
Department of Agriculture (Pretoria, 1916). Sir A. 
Theiler and W. Robertson describe the life-history of 
Trichostrongylus douglasi, a nematode parasite of the 
ostrich, somewhat unfortunately called a ‘* wireworm.” 
The four larval stages are carefully distinguished, and 
it is shown that the young worm can survive and be- 
come mature in the bird’s stomach only when swallowed 
in its late second stage. No evidence that the worms 
ever enter through the skin could be obtained. Dr. 
F. Veglia contributes an exhaustive paper on ‘‘ The 
Anatomy and Life-history of Haemonchus contortus,” 
a well-known strongylid parasite of the stomach in 
ruminants; in this memoir a number of structural and 
bionomic details are recorded. The photographs and 
careful drawings illustrating these reports are repro- 
duced in excellent style; it is all the more disappoint- 
ing to find that for the letterpress of these valuable 
zoological papers a cheap contract method has appar- 
ently been adopted by the South African Government 
which recalls the worst traditions of our Home Sta- 
tionery Office. 
THE LOUTREUIL FUND. 
GRANTS FOR SCIENTIFIC WORK, 
ps the Comptes rendus of the Paris Academy of 
Sciences for November 27 is given the report of 
the council of the Loutreuil Foundation. The grants 
allotted are divided into three groups, as follows :— 
I. ESTABLISHMENTS MENTIONED BY THE TESTATOR.— 
(1) Museum of Natural History. 2000 francs to Prof. 
Louis Roule for the continuation of his researches on 
the migratory fishes of French marine and fresh waters, 
the Salmonidez in particular. 10,000 francs for re- 
fitting the maritime laboratory of the Island of Tatihou 
at Saint-Vaast-La-Hougue. This laboratory has been 
used as a concentration camp since the outbreak of 
war, and considerable damage has been done. (2) The 
Collége de France. 700 francs to E, Gley to complete 
the frigorific installation for which an allocation was 
made last year. 4350 francs to Prof. Nageotte for the 
purchase of apparatus for pursuing his studies on the 
regeneration of nerves. 4000 francs to M. |’Abbé 
Rousselot for continuing and developing the experi- 
“ments commenced by him on locating artillery by 
