1 1 66 



INDEX 



oos 



Ob'spores, 540 ; of Volvox, 556 ; of Vau- 

 cheria, 563; of Achlya, 565; of 

 Sphceroplea, 572 ; of (Edogonium, 573 ; 

 of Chara, 579 ; of Fucacece, 628 



Ooze, Globigerina, organisms in, 811, 

 813, 820 ; compared with chalk, 1085 



Opalescent mirror as a substitute for 

 polarising prism, 194 



Opalina, 774 



Opaque illumination by side reflector, 333 



mounts, 336 



' Open ' bundles, 710 



Operculina, 830 ; and Nummulites com- 

 pared, 834 



Opercule of mosses, 671 



Ophiacantha vivipara, development of, 

 900 note 



Ophioglossacece, development of pro- 

 thallium of, 679 



Ophioglossum, sporanges of, 676 



Ophiothrix pentaphyllum, spines of, 

 891 ; teeth of, 892 



Ophiurida, mounting, 481 



Ophiuroidea, skeleton of, 891 ; spines of, 

 891; teeth of, 892; larva of, 898; 

 direct development in, 900 note 



Ophrydia, quantities of, 777 



Ophrydium, cellulose in zoocytium of, 778 



versatile, effect of light on, 775 

 Ophryodendron, 784 



Opium poppy, latex of, 695 



Optic axis of Powell and Lealand's No. 1, 



194 

 Optical anomalies in petrology, 1078 



centre, 24 



tube-length of microscope, 158, 159 

 Orals of Ahtedon, 901 

 Orbiculina, 803, 804, 808 



compared with Heterostegina, 834 

 Orbitoides, 835 



and Cycloclypeus compared, 835 



Fortisii, 836 

 Orbitolina, 824 



Orbitolincs, occurring with flint instru- 

 ments, 824 

 Orbitolites, 804-810 



shell of, 798 ; range of variation in, 

 810 ; structure of Parkeria resembling, 

 817 ; deposits of, 1085 



and Cycloclypeus compared, 801 



complanata, animal of, 807-809 



italiacv, 806 note, 808 



tenuissima, 808 

 Orbulina, 820 



Orbuline shell, sandy isomorph of, 815 



Orchidece, pollinium of, 722 



Orchids, mycropyle of, 723 



Orchis, pollen- tubes of, 723; seeds of, 

 724 



Organised structure and living action, 

 530 



Organs, 533 



' Organs of sense ' in Ciliata, 775 note 



Oribatidce, nymph of, 1009 ; mouth-parts 

 of, 1009 ; legs of, 1010 ; integument of, 

 1010 ; auditory organ, 1011 ; reproduc- 

 tive organs, 1011 ; supercoxal glands 



of, 1011 ; tracheae of, 1011 ; characters 



of, 1012 

 Orienting small objects for sectionising, 



499 



Origanum onites, seeds of, 724 

 Ornithorhynchus, hair of, 1081 

 Orobanche, seeds of, 724 

 Orthoptera, eyes of, 987 ; antennae of, 



988; wings of, 999 ; nymph of, 1009 

 Orthoscopic effect, 95 ; with Ramsden's 



circles, 106 



eye-piece, 376 



Orthosira Dickiei, sporangial frustule 



of, 595 



Oscillatoria, movement of, 547 

 Oscillatoriacece, 547 



movements of, 433 

 Oscula of sponges, 856 



Osmic acid and fatty structures, 517 

 Osmunda, sporanges of, 676 



regalis, prothallium of, 679 note 

 Ossein, of bone, 1023 



Ostiole of conceptacle of corallines, 632 



Ostioles of Naviculacece, 590 ; of Cijni- 

 bellete, 590 



Ostracoda, 960 



Ostreacece, shell of, 923 



Ostrich, egg-shell of, 1101 



Otoliths compared with artificial concre- 

 tions, 1100 



of Mollusca, 941 

 Ovarium of Polyzoa, 907 

 Over-amplification, 88 

 Over-corrected objective, 20 

 Over-correction, 358-360 

 Overton, on Volvox, 556 note 

 Ovipositor of Oribatidce, 1012 

 Ovipositors of insects, 1002-1004 

 Ovule of Phanerogams, 684 



suspensor of, 534 



structure of, 684-685 ; development of , 

 722 



Ovum of Hydra, 866 



Oxytricha, a phase in development of 



Trichoda, 780 

 Oxyuris vermicularis, 944 

 Oysters, shell of, 923 



Pacinian corpuscles, 1053 

 Palaeontology, use of microscope in, 1083 

 ' Palate ' of Gastropoda, 919, 930 ; classi- 



ficatory value of, 932 ; preparation of, 



932 ; viewed with polariscope, 933 ; 



bibliography, 933 

 Paleee of grasses, silex in, 715 

 Palisade-parenchyma of leaves, 716 

 Palm, stem of, 701 

 Palmella, as gonid of lichen, 651 

 cruenta, 558 



Palmellacece, 557 ; frond of, 558 

 Palmodictyon, 559 ; zoospores of, 559 

 Palmogloea macrococca, life-history of, 



541, 542 

 Palpicornia, antennae of, 988 



