484 Chronicles of Science. | July, 
matter. The fluids of the Annelida, though hardly comparable to the 
blood of the insect, also contain corpuscles, the intra-visceral fluid 
being the most remarkable on this account, whilst the respiratory fluid 
contained in distinct vessels is in general brightly coloured, and also, 
though less obviously, contains corpuscles. Dr. H. Landois has 
devoted considerable attention to the study of the blood of insects. 
By allowing the liquid to evaporate, he has succeeded in obtaining the 
various salts of the blood in a crystallized condition, and has been 
enabled thus to ascertain the nature of the mineral constituents of the 
blood in many of, the commoner forms of Coleoptera and Orthoptera. 
They are found to differ in various species, as does also the form of the 
blood corpuscle. 
We may notice here a form of microscope made by Mr. Ladd, of 
Beak Street, and specially adapted for use in museums and public 
galleries. Two of these instruments have for some time been in use 
in the Food Museum at South Kensington, and have answered their 
purpose most satisfactorily. The instrument is an ordinary compound 
microscope, with a revolving stage capable of receiving a dozen objects 
at the same time. By turning the disc, the objects are brought in suc- 
cession under the eye of the observer. The focus is kept fixed, as is 
also the reflector, so that an inexperienced person cannot disturb the 
arrangement, which may be made by one of the functionaries of the 
Museum. If such instruments as these were placed in the galleries of 
the British Museum and such places of public instruction, supplied 
with suitable objects, it would add greatly to their general usefulness 
and interest. Among the various works which have been published 
during the past quarter, for the purpose of assisting the student im the 
use of the microscope, is one by Dr. J. W. Griffith, conjoint author of 
the ‘ Micrographical Dictionary,’ entitled ‘An Elementary Text-Book 
of the Microscope.’ The figures, of which there are over four hundred, 
are very well executed, and contain drawings from among almost every 
class of objects likely to come under the student’s observation. We 
notice the work fully in another section of this Journal. 
The formation of societies intended to unite individuals engaged or 
interested in studies connected with the microscope must always be 
hailed with pleasure, as indicating an advance in the progress of 
Microscopical Science. A Microscopical Society has been formed at 
the University of Oxford, under the presidency of Dr. Acland, the 
Regius Professor of Medicine: many distinguished members of the 
university have joined the Society, and it is to be expected that an 
impulse will be given thereby to independent research, which cannot 
but lead to important results. 
MicroscoricaL Soctery or Lonpon. 
Although the meetings of the Society have been well attended during 
the past quarter, yet few papers of interest have been communicated. 
Dr. Greville, who has worked so indefatigably at the group of the 
Diatomacesw, continued his series of papers on “New and Rare 
