INDEX AND GLOSSARY 



Scleren chyma (<Ai?p6?, hard : ^yxv^a 



infusion) : Moss, 402 : Fern, 413, 416 

 Scyllium. See Dogfish. 

 Secre'tion (sccretits, separate), nature of, 



227 : formation of cell-wall a process of, 



T 4 

 Seed, formation and germination of, 459; 



476 

 Seg ment (segment wn, a piece cut off), in 



plants a node together with the next 



proximal internode, 205 : in animals the 



name is variously applied. See Meta- 



mere, Podomere. 

 Segment al cell: Nitella, 210: Moss, 



403 : Fern. 418 

 Segmentation, metameric. See Meta- 



mere. 

 SELAGINELL A (o-eAaye'w, to shine): 



Figures, 443, 445 ; general characters, 



442 : cone, sporangia, and spores, 444 : 



prothalli and gonads, 444 : development 



and alternation of generations, 446 

 Self-fertilization, applied to the sexual 



process when the gametes spring from 



the same individual, 199 

 Sep'alS (separ, separate), the outer or 



proximal perianth-leaves in the flower of 



Angiosperms, 464, 468 

 Sep tum (septntK, a barrier) : In Peni- 



cillium, 187 : in Polygordius, 277 : 



development of, 301 

 Set'a (seta, a bristle), 287 

 Sex-cells, primitive, 253 : origin of in 



Hydroids, 245 : in Polygordius, 290 

 Sexual differentiation, illustrated by 



Vaucheria, 172 : by Spirogyra, 199 

 Sexual generation. See Gamobmm. 

 Sexual reproduction, nature of, 42 

 Shell, Mussel, 350 

 Shoot, in plants, an axis of the second or 



any higher order with its leaves. 206 

 Sieve-tubes and plates, 418 



Sinus (sinus, a hollow) in Crayfish, a 



spacious cavity containing blood, 338 

 Sinus venosus, 384 

 Siphons, in- and ex-halant, 349 

 Skeleton. See Endo- and Exo-skeleton. 

 Skull, Dogfish, 374 

 Slime-fungi, See.Mycetozoa. 

 Solid aggregate, 203 

 Somat'iC (<ru>/u.a. the body), applied to the 



layer of mesoderm which is in contact 



with the ectoderm and with it forms the 



body-wall, 275 

 Sor'us (<rwp6s, a heap), an aggregation of 



sporangia, 422, 440 

 Species (species, a kind), meaning of term 



illustrated, 8, 137; definition of, 139: 



origin of, 141 



Specific characters, specific name. ?,. i ,<> 



Specialized, meaning of, 140 



Sperm (a-rrepfj-a., seed), the male or micro- 

 gamete in its highest stage of differentia- 

 tion ; structure and development of, 255 : 



see also under the various types, and 

 especially Vaucheria, 173 



Spermatozo id, spermatbzo on (<nre>fxa, 

 seed : (Jwoi/, animal, from the actively 

 moving sperms of animals having been 

 supposed to be parasites), synonyms of 

 sperm. 



Spermary ((rirepna., seed), the male gonad 

 or sperm-producing organ : see under the 

 various types, and especially Vaucheria, 

 172 



Sperm iduct (cnrc'pjua, seed : duco, to lead), 

 a tube conveying the sperm from the 

 spermary to the exterior, 292 



SpermatOgen'esiS (arrep/u-a, seed ; yeVeo-is, 

 origin), the development of a sperm from 

 a primitive sex-cell, 254 (Figure) 



Spinal cord, Dogfish, 391 



Spiral vessel See Vessel. 



SPIRILL'UM (spira, a coil) 86, 88 (Figure) 



SPIROGYRA (spiia, a coil : gyrus. a revo- 

 tion) : Figure, 195 : occurrence and 

 general characters, 194 : microscopic 

 structure, 194 : growth, 197 : conjugation, 

 198 : development, 200 : nutrition, 200 



Splanch'nic (&ir\dyxvov, intestine or vis- 

 cus), applied to the layer of mesoderm 

 which is in contact with the endoderm 

 and with it forms the enteric canal, 275 



Spontaneous generation. See Abio- 



genesis. 



Sporan gium (a"iropd, seed : dyyelov, a 

 vessel), a spore-case: Mucor, 160 : Vau- 

 cheria, 171 : Fern, 422. See also Mega- 

 and Micro-sporangium. 



Spore ((TTropa, a seed), an asexual repro- 

 ductive cell : see under the various types 

 and especially Heteromita, 42 : Saccha- 

 romyces, 74 : Bacteria, 89 : vitality of 

 in Bacteria, 99, 101 : Pemcillium, 189 : 

 Moss, 407 : Fern, 423. See also Mega- 

 and Micro-spore. 



Sporogon'ium a-nopd seed : yovos, pro- 

 duction), the agamobiumofa moss, 407 



Spor'ophyll (a-iropd, seed : (|>uAAor, leaf), 

 a sporangium-bearing leaf: Equisetum, 

 436 : Selaginella, 444 : Gymnosperms, 

 454^ 455 ' Angiosperms, 466, 471 



Stamen (stamen, a thread), a male sporo- 

 phyll, 454, 456, 466 



Starch, composition and properties of, 27 



STARFISH : Figures, 307-317 : general 

 characters, 305-310 . radial symmetry, 

 306 : tube-feet and ambulacral system, 

 307, 313: exoskeleton, 310: nervous 

 system, 315 : reproduction and develop- 

 ment, 315-317 



Stem, structure of : Moss, 402 ; Fern. 413 : 

 Gymnosperms. 448 : Monocotyledons, 

 462 



Sterig'ma (a-Trjpiy^a, a support): Pcni.il 

 Hum. 188 ; Agaricus, 193 



Sterilization of putrescible infusions, 99- 



