GLOSSARY 127 



Scle'robase (Gr. skleros, hard ; basis, a foundation). The hard 

 chitinous or calcareous material which forms the central 

 portion of the common stem in some compound Actinozoa. 



Scleroder'mite (Gr. skleros, hard; derma, skin). The hard 

 calcareous skeleton in the Crustacea ; also applied to the 

 coral which is formed within the tissues of the reef- 

 building polypes. 



Sclero'tic (Gr. skleros, hard). The thick outer tunic of the 

 eyeball. 



Scle'rotome (Gr. skleros, hard ; tenuio, I cut). Partitions which 

 in some Vertebrata, especially fishes, separate the muscles 

 into zones. 



Scrobi'culus cor'dis (L. scrobiculus, a small pit ; cordis, of the 

 stomach). The pit of the stomach, a depression in the 

 upper part of the epigastric region. 



Scro'tum (L. a hide). The bag which in the higher Vertebrata 

 contains the testes. 



Scu'ta (L. a shield). The lower or proximal pieces of the 

 valves in the Cirripedia, by which the cirri pass out from 

 the body. 



Scu'ta buccalia (L. scuta, a shield ; bucca, the cheek). A 

 series of five plates situated near the mouth in the 

 Ophiuridea. 



Scute (L. scuta, a shield). The dermal defences or scales of 

 some Vertebrata. 



Seba'ceous (L. sebum, suet). The name given to certain glands 

 of the skin which secrete an oily material for the lubrica- 

 tion of the hairs. 



Secre'tion (L. secerno, I separate, set apart). The process of 

 separation of materials from the blood, together with the 

 formation of fresh substances from those materials for 

 further use in the economy; also used to signify any 

 substance secreted. 



Secto'rial teeth (L. sector, scctoris, a cutter). The fourth 

 praemolar teeth of the dog; so called because the prse- 

 molars of the lower jaw bite like scissor-blades against 

 those of the upper jaw. 



Secun'dine (L. secundus, second). The inner coat of the ovule 

 of a plant. 



Sela'chii (Gr. seldchos, a sort of cartilaginous _fish). A sub- 

 division of the cartilaginous Plagiostome fishes which 

 comprises the sharks. 



Se'men (L. seed). The reproductive fluid of the male. 



