INDEX. 



819 



O. 



Oaks, Disease, 84 

 Obituary, Ernst Abbe, 156 

 Object-glass, New Formula, 499 

 Objective, Abbe Condenser UBed as, 644 



— Spencer, 103 

 Objectives, Leitz' New, 500 



— Microscopical, Notation, 500 



— Keicbert's, with Bourguet's Spring 



Safety Action, 249 



— See Contents, xxxiii 



— Symmetrical Optical, Theory, 501 



— Telescope and Microscope, Discrepancy 



between Diffraction Theory and 

 Geometrical Optics in Actual In- 

 stances, 644 

 Object-Stage, with Sliding Measurement 



Adjustment, 497 

 Oceanu, P., Influence of Ovariotomy in 



Goat, 423 

 Ocelli in Periplaneta and Cloeon, 307 

 Ocular, Camera, Leitz', 502 

 GSdogonium, 79 

 Oenogyna baeticum, 308 

 GCstrid Larva, New, from Hippopotamus, 



433 

 CEstrous Cycle in Ferret, 34 

 Oil, Essential, Distribution in an Annual 



Plant, 67 

 Olfactory and Auditory Sense of Spiders, 

 309 



— Buds in Vertebrates, 169 



— Cells of Lamprey, 296 



— Organ, Development in Spinax niger, 



167 



of Lamprey, Development, 577 



" Olfactory Seta?," so-called, of Cladocera, 



437 

 Oligochaeta, Genital Ducts, 56 



— of Lake Baikal, 594 



— Vascular System, 700 

 Olive Trees, Disease, 619 



Oltmanns, F., Morphology and Biology of 

 Algae, 76 



Omelianski, W., Formate Broth in the 

 Differential Diagnosis of Micro- 

 organisms, 657 



— New Colourless Thiospirillum, 629 

 Oogenesis and Development of Fasciola 



hepatica, 78 



— in Vaucheria, 78 



— of Branchellion, 595 



Opalina ranarum, Longitudinal Division, 

 323 



Opalinid, New, 61 



Opaque Objects, J. E. Stead's Illuminator, 

 372 



Ophioglossaceae and Marsiliaceaj, Affini- 

 ties, 454 



Ophioglossum vulgatum, Prothallium, 202 



Ophiuroid, Gall-forming Annelid, 700 



— New Devonian, 319 



Opisthenogenesis, Notes, 295 

 Opisthorchis felineus, Abnormal Alimen- 

 tary System, 57 

 Optical Aberrations, Specification and 

 Measurement, 563 



— Bench and Large Camera, 26S 



— Contact, Microscopical Determination 



of the Position of a Reflecting Sur- 

 face during, 756 



— Convention, The, 559 



— Dictionary, 374 



— Glass, Possible Directions of Progress, 



572 



— Instruments, Consideration of the 



Equivalent Planes, 560 



Czapski's Elements of the Theory, 



653 



— Paradox, 417, 557 



— Problems, Application of the Undula- 



tory Theory, 401 



— Properties of Glasses produced by 



Cbance Brothers, 654 

 Optics, Geometrical, Von Rohr's Image- 

 formation from the Standpoint of, 

 654 



— Microscopical. See Contents, xxxv 

 Opuntia, Notes on the Fruits, 451 

 Orchids, German, Illustrations, 70 

 Orestias, Inferior Pharyngeal Bones in 



Genus, 175 

 Organ-Formation and Polarity in Caulerpa 

 prolifera, 465 



— Peculiar, in Phryganids, 694 

 Organisms, Origin of Markings, 302 

 Organs of Pyrenomycetes and Deutero- 



mycetes, Nomenclature, 476 

 Oribatid Mites from Neighbourhood of 



Cambridge, 53 

 Oribatidae, Exhibition of Slides, 398 

 Orthogenetic Variation in Chelonia, 



Gadow's Hypothesis, 581 

 Ortmann, A. E., Affinities and Distribution 



of Cambarus, 697 

 Osborn, H. L., Habits and Structure of 



Cotylaspis insignis, 317 

 Osmond, F., Scientific Development of the 



Art of Polishing, 535 

 Osseous Tissue, Peculiar, of Sunfish, 



170 

 Ostenfeld, C. H., Studies on Phytoplank- 



ton, 210 

 Osteologv, Comparative, of Accipitres, 

 428 



— Cranial, of Fishes. 45 



Ostergren, H.. Korean Holothurians, 704 



— Northern Synaptids, 599 

 Osterhout, W. J. V., Fixation in Vacuo, 



527 



— Imbedding Microscopic Alga?, 530 

 with Incomplete Dehydration, 526 



— Rapid Method of Mounting in Aqueous 



Media, 532 



— Simple Freeziug Microtome, 528 



3 I 2 



