INDEX 



1149 



DIA 



markings of, 593 ; binary division 

 of, 594-597 ; reproduction of, 594-601 ; 

 placochromatic, 598 ; coccochroraatic, 

 598 ; conjugation of, 599 ; zj-gospores 

 of, 599 ; gonids of, 599 ; movements of, 

 liOl ; classification of, 602 ; habits of, 

 619 ; habitats of, 620 ; distribution of, 

 621 ; fossil forms of, 622 ; used as 

 food, 622 ; collecting, 622 ; cleaning, 

 623, 624 note ; mounting, 624 ; as food 

 of Ciliata, 775 ; in mud of Levant, 

 1085 



Diatom-frustules in ooze, 1086 



Diatomin, 587 



Diatoms in stomach of ascidians, Holo- 

 tliiirice, &c., 614, 623 



Diatoms. See DIATOMACE* 



Dichroisrn, 1098. See PLEOCHROISM 



lUrldea, 602 



Dicotyledonous stems, fossilised, 1083 



DICOTYLEDONS, 700 ; stem of medullary 

 rays of, 702 ; epiderm of, 712 



Dictyocalyx pumiceus, 861 



Dictyochya fibula, 620 



Dic.tyocysta, silicious shell of, 773 



Dictyoloma peruviana, winged seed, 

 724 



Dictyospyris clathms, 847 



Dicti/ota, oijspheres of, 627 



Didemnians, 914 



Dlflijmium serpula, plasinode of, 635 



Differential screw, Campbell's fine ad- 

 justment, 162, 164, 165, 174, 202, 230 



Differential staining, 493 



Differentiation of cell, 533 



Difflngia, 746 ; test of, 746 



Diffraction, 62 



Abbe's theory of, and homogeneous 

 immersion, 363 



- Fraunhofer's law, 57 



rays are image-forming, 59 



- spectra, 28, 67 ; phenomena, 62, 6 1 ; 

 image, 64, 72 ; experiments, 66-70 ; fan 

 of isolated corpuscles, 72 ; problem, 73 ; 

 pencil, 74, 75 ; hypothesis of Abbe, 74 ; 

 fan, 75 ; theory, application of, 70, 78 ; 

 bands, 277 ; phenomena, Abbe's experi- 

 ments, 434 ; ghost, 435 



Digestive vesicles of Cilia fa, 776 



Digitalis, seeds of, 724 



Dimorphism in Foraininifent, 802 



Dinobryon, 765 



Dinqflagellata, 770 



Dinomastigophora, 770 note 



Dioptric investigations by Gauss, 106- 



110 



Dioptrical image, 30, 72 

 Diorite, fluid inclusions in, 1074 

 Dipping tubes, 350 

 Diptera, 973 ; eyes of, 987 ; aiiteunfe of, 



988 ; mouth-parts of, 990 ; wings of, 



998 ; ovipositor of, 1003 ; imaginal discs 



of, 1007 



Direct division of nucleus, 538 

 ' Directive vesicles ' of egg of 



937 

 Disc-holder, Beck's, 339 



DYT 



Discida, 849 



Discoliths, 748, 749 ; artificially produced,. 



1101 

 Jt/xrurliina, 824 



globularis, 798 



Disintegration of rock-masses, 1076 

 Dispersion, 9, 17 ; in glass, 31 



and desiccation of encysted Ciliata, 

 781 



Dispersive power, 2, 9, 18 ; of flint glass, 



10 

 Dissecting apparatus, 455 



microscope, Greenough's binocular, 

 248 ; Stephenson's binocular, 248 ; 

 Huxley's, 251; Zeiss's, 251, 253 

 Bausch and Lomb's, 252 



Distance of projection of image, 26, 27 

 Distinct vision, 26 

 Distoma, life-history of, 946 



hepaticum, 945 

 Divergence of light, 18 



Divini's compound microscope, 129 

 Division, binary, of cells, 535 ; of desrnids, 

 582 



artificial, of ActinospJieerium, 741 note 



of naiads, 955 

 Dobie's line, 1049 

 Dog-fish, scales of, 1028 



D'Orbigny, on plan of growth of Fora- 



ininifera, 799 

 Doris, spicules in mantle, 928, 929 ; nida- 



mentum of, 934 ; eggs of, 942 ; spines 



of, imitated, 1101 

 - bilameUata, development of, 935- 



937 



ji/iosa, palate of, 931 



tuberculata, palate of, 931 



Double illumination, Stephenson's me- 

 thod, 105 



Doublet, Wollaston's, 36, 153 

 Dragmata, of sponges, Ntio 

 Dragon-flies, wings of, 998 

 Dragon-fly, facets in eyes of, 983 



Sec Libflliila 

 Drapamaldia yloinerata, 574 

 Draw-tube of microscope, 157 

 Drebbel's modification of Keplerian 



telescope, 121 



Dredge, 528 



Drepanidium ratian/ui, 752 



Drone-fly. See Erixtuli*. 



Dropping-bottle, 476 ; German, 477 ; ex- 

 pansion, 477 



Drosera, glands of, 714; seeds of, 724 



Dry-mounting, Smith's ' cells ' for, 446 



Ducts of Phanerogams, 698 



Dudrcniiiii/a, fertilisation in, 632 ; ferti- 

 lising tubes, 632 



Dajardin, on ' sarcode,' 530 iiutc 



separates Ai/ueba from Infusoria, 

 733 



Duiining's zoophyte trough, 348 

 Duramen, 704 



Dwarf-male of CEilar/niti/nii, 572 

 Di/tiscus, eye of, 987 ; antennas of, 988 ; 



spiracle of, 996 ; trachea of, 996 ; foot 



of, 1001, 1002 



