SPI- 



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SPL- 



spiracle (spl'rakl) n. [L. spiraculum, 

 an air-hole.] The first pharyngeal 

 aperture or visceral cleft (emb.) ; the 

 branchial passage between man- 

 dibular and hyoid arches in Fishes ; 

 a lateral branchial opening in tad- 

 poles ; a nasal aperture of a 

 Cetacean ; a respiratory aperture 

 behind the eye of Skates and Rays ; 

 a breathing aperture of Insects 

 (zool.). 



spiracular (spirak'ular) a. [L. spir- 

 aculum, an air-hole.] Pert, a 

 spiracle (zool.). 



spiraculate (sptrak'ulat) a. [L. 

 spiraculum, an air-hole.] Having 

 spiracles (zool.). 



splraculiferous, spiraculate. 



spiraculiform (splrak'ulifdrm) a. 

 [L. spiraculum, an air-hole ; forma, 

 shape.] Spiracle-shaped. 



spiraculum (spirak'ulum) n. [L. spir- 

 aculum, an air-hole.] A spiracle. 



spiral (spfral) a. [L. spira, a coil.] 

 Winding, like a screw ; appl. leaves 

 alternately placed ; appl. flower 

 with spirally inserted parts (dot.'). 



spiral, oblique, or alternating: cleav- 

 age, cleavage into unequal parts, 

 arranged in mosaic fashion and 

 interlocking, the upper cells being 

 rotated to the right to alternate 

 with the lower (cyt.). 



spiral valve, in all Fishes except 

 Teleosts, a spiral infolding of the 

 intestine wall, increasing the ab- 

 sorptive surface (zoo!.). 



spiral vessels, the first xylem 

 elements of a stele, spiral fibres 

 coiled up inside tubes and so 

 adapted for rapid elongation (dot.). 



spiranthy (splran'thi) n. [L. spira, 

 coil ; Gk. anthos, flower.] Dis- 

 placement of flower parts through 

 twisting (bol.). 



spiraster (splras'ter) n. [L. spira, 

 coil ; aster, star.] A spiral and 

 rayed sponge spicule (zool.). 



spire (splr) n. [L. spira, coil.] The 

 totality of the whorls of a spiral 

 shell (zool.). 



splreme (spfrem) n. [Gk. speirema, 

 a coil.] That stage in mitosis 

 when the nucleus chromatin appears 

 in the form of a thread, continuous 

 or segmented (cyt.). 



spiricles (spfriklz) n. flu. [L. spira, 



coil.] Thin, coiled, thread-like 

 outgrowths of some seed - coats 

 (bot.). 



splriferous (splrif'e'rus) a. [L. spira, 

 a coil ; /erre, to bear.] Having a 

 spiral structure. 



spirillar (splril'ar) a. [L. spirillum, 

 a small coil.] Pert, a spirillum. 



spirillum (splril'um) n. [L. spirillum, 

 a small coil.] A thread - like 

 Bacterium ; a motile filament in .1 

 cryptogam antheridium (hot.). 



spiriyalve (spfrivalv) n. [L. spira, 

 coil ; valvae, folding doors.] A 

 Gastropod with spiral shell (zool.). 



spiroid (spl'roid) a. [L. spira, coil ; 

 Gk. eidos, resemblance.] Spirally 

 formed. 



spironeme (spfronem) n. [L. spira^ 

 coil ; Gk. nema, thread.] The 

 coiling or twisting thread in an 

 Infusorian stalk (zool.). 



spirulate (splr'ulat) a. [L. spira, 

 coil.] Appl. any spiral structure or 

 coiled arrangement. 



splanchnic (splangk'nik) a. [Gk. 

 splangchnon, an entrail.] Pert. 

 the viscera ; appl. nerves (anat.). 



splanchnocoel (splangk'nosel) n. [Gk. 

 splangchnon, an entrail ; koilos, 

 hollow.] The cavity of the lateral 

 plates of the embryo, persisting as 

 the visceral cavity of the adult 

 (emb.). 



splanchnology (splangknfil'bjl) n. 

 [Gk. splangchnon, an entrail ; logos, 

 discourse. J The branch of Anatomy 

 dealing with the viscera. 



splanchnopleure (splangk'noploor) n. 

 [Gk. splangchnon, an entrail ; pleura, 

 side.] The alimentary canal wall, 

 formed from the splanchnic layer 

 of the mesoblast and the hypoblast 

 (emb.). 



spleen (splen) n. [Gk. splen, the 

 spleen.] A vascular ductless organ 

 situate beneath the diaphragm to 

 the left of the stomach (anat.). 



splenetic (splgngt'lk) a. [Gk. splen, 

 spleen.] Pert, the spleen. 



splenial (sple'nlal) a. [L. splenium, 

 a patch.] Pert, the splenius muscle 

 (anat.), or splenial bone (zool.). 



splenial bone, a membrane bone in 

 the lower jaw of Reptiles. 



splenic (splgn'lk) a. [Gk. splen, the 

 spleen.] Pert, the spleen. 



