CONTENTS. Til 



PAGE 



XXXIV. — New Species and Varieties of Diatomaceae from the 

 Caspian Sea. By A. Grunow, Hon. F.R.M.S. Translated 

 with additional Notes by F. Kitton, Hon. F.R.M.S. 



(Plate XXI.) No. 6 677 



XXXV.— On the Morphology of Vegetable Tissues. By W. H. 



Gilburt, F.R.M.S. (Plates XXII. and XXIII.) .. .. No. 7 801 



XXXVI. — Note on the Structure of the Scale of a Species of the 



Genus Mormo. By Joseph Beck, F.R.M.S „ 810 



XXXVII. — On New Methods for Improving Splierical Correction, 

 applied to the Construction of Wide-angled Object- 

 glasses. By Professor E. Abbe, of Jena, Hon. F.R.M.S. 



(IfigO „ 812 



XXXVIII. — On the Anatomj' of Leptodora hyalina. By H. E. 



Forrest. (Plates XXIV. and XXV.) „ 825 



XXXIX. — On a New Species of the Genus Eucampia. By 



Henry Stolterfoth, M.D. (4 figs.) „ 835 



XL. — Immersion Stage Illuminator. By John Mayall, jun., 



F.R3I.S. (1 fig.) „ 837 



XLI. — On a Table of Numerical Apertures, showiug the 

 Equivalent Angles of Aperture of Dry, Water Immer- 

 sion, and Homogeneous Immersion Objectives, with their 

 respective Resolving Powers, taking the Wave Length 

 of Line E as the Basis ; a = n sin. u\ n = refractive 

 index, and w = ^ anjile of aperture. By J. W. Stephenson, 



F.R.A.S., Treas. R.M.S , 839 



XLII. — Aperture Measurements of Immersion Objectives ex- 

 pressed as " Numerical Aperture." By John Mayall, 

 jun., F.R.M.S „ 842 



Record of CuBREirr Researches belating to Ixvertebrata, Cryptogamia, 

 Microscopy, &c., iNCLrDiNG Embryology and Histology generally. 

 ( = Notes and Memoranda in Nos. 1 to 4) : — 



ZOOLOGY. 



A. — General, including Embryology and Histology of the Vertebrata. ^^^^ 



" Gell-Soul and Cellular Psychology " No. 1 53 



The Striicture of Blood-vessels „ 82 



Cells and their Vital Fhenotnena No. 2 137 



Influence of the different Colours of the Spectrum on Ani- 

 mals and Plants „ 138 



Nuclei of the Blood-corpuscles of the Triton No. 3 272 



Division of Cartilage Cells „ 273 



Infltience of the different Colours of the Spectrum on 



Animals „ 273 



Primitive Stripe in the Chick No. 4 395 



Evolution of the Male and Fetnale Genital Glands of 



Mammalia i, 397 



Natural Science Prizes of the Brussels Academy .. ., „ 397 



Cells and Nuclei „ 397 



Nucleus in Blood'corpuscles No. 5 545 



6 2 



