652 



Nerve-ring, of Asterias rubens, 444, 447 ; 

 of Ophiothrix fragilis, 488 ; of Echinus 

 esciilentus, 518, 521, 527 ; of Antedon 

 rosacea, 583 ; outer, of A. rosacea, 585 



Nervous fibrils in Ciliata, 143 



Nervous system, in Animals, not in Plants, 

 39 f . ; of Asterias rubens, 444 f . ; of 

 Ophiothrix fragilis, 488 ; of Echinus 

 esculentus, 518 f. ; of Holothuria nigra, 

 566 ; of Antedon rosacea, 583 f. 



Neuron, 444 



Neurophane { = supposed nervous fibrils in 

 Ciliata), 143 n. 



Newts, Trichodina parasitic in, 158 



Nitriles in relation to nutrition, 36 



Noctiluca, 110, 132 f.; endosarc, 144 ; X. 

 miliaris, 133 



Mdosaria, 59, 63, 66 f. 



Nosema, 98 ; X. homhycis, 107 ; organism 

 of pebrine, 107 



Nubecxilaria, 59 



Nuclear apparatus, of Infusoria, 48, 136 ; 

 of Ciliata, 139 f., 144 f. ; of diffused 

 granules, in marine Ciliata, 144 n. ; of 

 Suctoria, 159 : — bipartition in Tricho- 

 sphaerium, 54 : — reduction of Actino- 

 sphaerium, 75 n. ; of Monocystis, 96 ; 

 of Coccidiaceae, 100, 104 f. ; of Acysto- 

 sporidae, 104 f. ; of Myxosporidiaceae, 

 107 ; of Flagellates, 116 n. : — divisions, 

 in spores of Lankesteria, 95 — see also 

 Mitosis, Karyokinesis 



Niiclearia, 70 



Nuclein mass (=:karyosome), 24 



Nucleinic acid, 7 u. 



Nucleole, nucleolus, 7, 24, 25 f., 27 ; of 

 Sea-urchin ovum, 7 ; of Sphaerella, 

 126 



Nucleolidae, 554 



Nucleolites, 554 



Nucleoplasm, 6 



Nucleoproteids, 12 



Nucleus, 6 ; of cell, 6 f. ; of Amoeba, 5 f. ; 

 of A. polypodia, 10 ; resting, function 

 of, 24 n :— in mitosis, 25 f. , 27 f. ;— of 

 Euglypha, 29 ; of Paramecium cau- 

 datum, 148 : — pairing state of, 34 ; of 

 Ciliata, 150 f. ; of Paramecium ca\i- 

 datum, 148 :— of Rhizopods, 52 ; ofPelo- 

 myxa, 52 ; of Microgromia socialis, 60 ; 

 of Foraminifera, 62 ; of mega- and micro- 

 spheric forms of Foraminifera, 68 f. ; of 

 Heliozoa, 71, 72, 74 ; of Clathndina, 

 74 ; of Radiolaria, 76 ; of Collozoum 

 inerme, 76 ; of Myxomycetes, 92 ; of 

 Sporozoa, 95 f. ; of Gregarines, 95 f., 

 98 f. ; of Bodo saltans, 117 ; kineto-, of 

 Trypcmosomanoctuae, 120, 121 ; trophic, 

 of T. nocttiae, 120 ; of Choanoflagellates, 

 122 ; of Opalina, 123 ; of Maupasia, 

 124 ; of Sphaerella, 126 ; of Volvox, 

 126 ; of Noctiluca, 133 : — fusion- or 



zygote-, 150 ; oi Paramecium caudatum. 



148 — see also Megauucleus, Micronucleus, 



Gametonuclei, Nuclear apparatus 

 Nuda, 423 

 Nummulitaceae, 59 

 Nummulites, 59, 63, 70 

 Nussbaum, on regeneration in Protozoa, 



35 11. ; on Hydra, 254 

 Nutrition, 9 ; animal and A'egetal, 35 f. ; 



of Flagellates, 110 f., 113; of Dino- 



flagellates, 130 f. — see Holozoic, Holo- 



phytic, Saprophytic:^ — of Alcyonaria, 



339 

 Nutritive function of granular cytoplasm of 



muscle-cell, 19 

 Nuttall, history of discoveries on Acysto- 



sporidae, 103 

 Nutting, 276, 280 n. 

 Xyctotherus, 137 ; habitat of, 152 



Obelia, 2S0 



Oceanapia, 223 



Ocellus, 252 



Octactine, 200 



Octactinellida, 20S 



Octot/emacis, 34(^ 



Ocular plate of Echinus esculentus, 512 



Oculina, 399 



Oculinidae, 399 



Ocyroe, 4^0 ; 0. crystallina, 419 



Ocyroidae, 4~^^ 



Odinia, 474, 476 



Oecology of Protista, 43 



Oesophagus, of Asterias rubens, 438 ; of 

 Echinus esculentus, 516 ; of Holothuria 

 nigra, 562 ; of Antedon rosacea, 583 ; 

 of Dipleurula, 605 



Ogilvie, M., 401 n. 



Oikomonadidae, 111 



Oikomonas, 111, 112 



Oil-drops, of Radiolaria, 79 f. ; luminous, 80 



Oil-globules, 37 ; of Ciliata, 144 



Oleocyst, 305 



Oligotrichaceae, 137, 155 



Olindias, 291 ; 0. mulleri, 291 



Olindiidae, 289, 291 



Olindioides, 291 ; 0. formosa, 291 



Olynthus, 185 



Omne vivum, ex ovo, 42 ; ex vivo, 44 



Onychaster, 203 



Onychaster, 502 



Oocyte (a cell which by unequal divisions 

 or mere nuclear divisions becomes con- 

 verted into an oosphere), 100 



Oogamete of Coccidiaceae, 100 f. 



Ookinete {active zygote) or oosperm, of 

 Acystosporidae, 104 f. ; of Trypano- 

 soma noctuae, 120 



Oolitic limestones, nucleus of concretions 

 of, 70 



Oosperm, 34 ; of Sporozoa, 96 f. ; of Volvox 

 globator, 127 f. 



