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[Monthly Microscopical 
Journal, Aug. 1, 1869. 
NEW BOOKS, WITH SHOKT NOTICES. 
Entozoa: being a Supplement to the Introduction to the Study of 
Helminthology. By T. Spencer Cobbold, M.D., F.E.S. London : 
Groombridge, 1869. — Those of our readers who already possess 
Dr. Cobbold's larger treatise will be glad to see this supplement 
to so excellent a treatise on Entozoa. In some respects it brings 
down the original work to the present date, but in others it may 
be regarded as an independent work containing some valuable 
special chapters on questions connected with parasites. The section 
devoted to the history of the discovery of Trichina is very in- 
teresting. In it the author collates the evidence bearing on the 
point under discussion, and we think shows very satisfactorily 
that Mr. Paget must be regarded as the original discoverer of 
this entozoon. His concluding remarks are very significant, and 
allude indirectly to the tendency on the part of certain very 
distinguished biologists to slur over the work of their fellow- 
countrymen. They refer the reader in search of fuller infor- 
mation to the original letters on the subject, the sources of which 
are stated in the copious bibliography which the author appends 
to the volume, and they terminate in the following pregnant 
sentence, "There are persons on this side the Channel who 
systematically ignore the labours of their own countrymen." 
The second chapter is also of interest, as it records a number 
of experiments (twenty-nine) made on birds and mammals 
with the muscles of a Trichinised subject. These experiments 
bear out those made by Pagenstecher and others, in proving 
that the Trichinaa do not find a favourable nidus for their deve- 
lopment in the intestines of birds, or at least do not pene- 
trate the blood-vessels of the alimentary canal in these animals. 
A good many of the trials on mammals failed in giving absolute 
results, but some of them were so distinctly successful that 
they leave no doubt as to the cause of the Entozoa. The chapter 
of the work which will most interest the microscopist is that 
which refers to the peculiar bodies which were found in the flesh of 
animals which died of the rinderpest. Some histologists regarded 
these as being in some way or other connected with this disease, 
but Dr. Col^bold gives numerous observations to show that they 
are as often present in healthy as in diseased animals, and he 
cites various experiments made upon himself to show that they are 
perfectly harmless. He regards these bodies as Psorospermise, and 
gives the following account of their microscopic characters : — " The 
bodies are enclosed in a well-defined transparent envelope, and 
even under low magnifying powers their contents exhibit more or 
less distinct indication of segmentation. In some specimens the 
segments display themselves as a distinct cell-formation, the con- 
tents of each individual cell being uniformly granular. Even 
under the i-inch objective the contained granules are clearly 
