GLOSSARY OF TECHNICAL TERMS xxxvii 



SPERMATOZOON (Gr. o-Trep/xa, sperm ; Cyov, a living being), the 

 term applied to a male gamete or germ cell when differen- 

 tiated as a free-swimming, active organism. 



SPICULES (Lat. spiculum, a little sharp point), minute mineral 

 bodies, usually of definite shape, secreted by special cells and 

 forming the skeleton of many invertebrate animals (e.g., 

 certain sponges). 



SPIREME (Gr. a-ntLpwa, coil), the coiled thread of chromatin sub- 

 stance which occurs at a certain stage in mitosis. 



SPLANCHNOPLEUEE (Gr. o-n-Aayx^a, viscera; irXevpd, side), the gut 

 wall, as opposed to the body wall. 



SPONTANEOUS GENERATION, the (supposed) origin of living things 

 from not-living matter. 



SPORANGIUM (Gr. a-iropd, seed ; ayyetor, vessel), a capsule in 

 which spores are produced. 



SPORE (Gr. a-iropd, seed), a single cell which is capable of giving 

 rise without any sexual process to a new individual (e.g., in 

 ferns) ; absolutely different from a true seed. 



SPOROPHYLL (Gr. cnropd, seed ; (f>v\\ov, leaf), a spore-bearing 

 leaf. 



SPOROPHYTE (Gr. a--opd, seed ; fyvrov, plant), the asexual, spore- 

 producing generation in certain plants (e.g., ferns and 

 flowering plants). 



SPORT, a suddenly appearing variation ; a mutation. 



STAMENS (Lat. stamen, thread), the modified leaves which form 

 the " male " organs of a flower. 



STAMINODES (Lat. stamen, thread ; Gr. eTSoj, form), imperfect 

 stamens. 



STATOBLAST (Gr. araros, standing ; jSAaoros, bud), a dormant bud, 

 protected by a special envelope ; found in certain fresh-water 

 invertebrates. 



STIGMA (Gr. o-rty/ua, spot), the moist spot on the end of the style 

 of a flower, on which pollen is deposited. 



STOMA (Gr. orojua, mouth), a minute opening in the epidermis of 

 a leaf, leading into air spaces in the mesophyll. 



STRATIFIED (Lat. stratum, pavement), arranged in layers. 



STYLE (Gr. or{5Ao9, pillar), part of the " female " organs of a 

 flower, bearing the stigma. 



SUPRASCAPULA (Lat. supra, above ; scapula, shoulder blade), a bone 

 or cartilage which lies above the scapula in the shoulder 

 girdle. 



