190 NOTES AND MEMOBANDA. [jou"rni'; mLVTi%1' 
The Homologies of the Dental Plates and Teeth of the Proboscidiferous 
Mollushs. — This is an excellent paper in the 'Annals' for February, 
by Dr. J. Denis Macdonald, F.R.S. The paper is accompanied by a 
plate. 
Comparative Anatomy and Physiology of the Betina. — Those of our 
readers who desire to familiarize themselves with the work that has 
been done up to the present on this important subject, should read 
the able review (by a well-known provincial anatomist) in the last 
(January) number of the 'British and Foreign Medico-Chirurgical 
Review.' It is certainly the most comprehensive and lucid exposition 
of a complex question that we have seen for some years. 
NOTES AND MEMORANDA. 
A "New Mnch Object-glass has been constructed by Mr. Chas. 
Collins, of Great Titchfield Street, and deserves the attention of 
working microscopists. It is especially adapted to investigations on 
Foraminifera, &c.; but it works admirably with certain anatomical 
preparations. It has a low angle (40°) of aperture, but gives an 
excellently flat field, and has great penetration. It bears the test of 
the three eye-pieces well, and is in all respects an admirable working 
lens. Mr. Collins does not intend this glass to be employed in diatom 
work, for which some think a J-inch suitable ; nevertheless, it works 
well with the Podura scale. Messrs. Powell and Lealand made an 
objective of the kind some years since, but they did not, we believe, 
follow up the manufacture. Mr. Collins has revived the idea ; and we 
think that naturalists and medical men will find his J-inch a most 
useful one. 
^iiekett Club Reports.— Mr. John Hopkinson requests us to 
correct an error which occurred in the report in our last issue. At 
page 133, line 15, the word "race" should be "Hydrozoa," and at 
line 21 the word "Asterida" should be "Actinozoa." It is only fair 
to ourselves to state that these were not printer's errors, but existed 
in the original "copy." As we are extremely anxious to avoid mis- 
takes, we trust that the secretaries of societies will read their reports 
carefully before transmitting them to us for publication. 
The Old Change Microscopical Soiree.— At this gathering, the 
number and interest of the microscopic objects exhibited far exceeded 
the average of such meetings. The " Synopsis" which was circulated 
among the guests was admirably arranged. It ought to be adopted at 
every such assembly, as it enables a visitor, who cannot possibly 
examine some thousand objects, to select with ease those specimens in 
which he feels a particular interest. 
Tinting Vegetable Tissues.— Some interesting observations on this 
point have been made recently by Dr. W. R. M'Nab. These we hope 
to lay before our readers in an early number. 
