128 GLOSSARY. 



Semilu'nar (L. half- moon-shaped). Applied (amongst other 

 things) to the valves of the veins and of the pulmonary 

 artery and aorta. 



Semimembrano'sus (L. half-membranous). One of the dorsal 

 muscles of the femur. 



Semipen'niform (L. half-feather-shaped). A term applied to 

 some muscles which bear a partial resemblance to the plume 

 of a feather. 



Semispinalis (L. half-spinal). One of the dorsal muscles of the 

 trunk. 



Se'mita (1+ a. narrow path). Bands of modified spines found 

 in the Echinidea. 



Semitendino'sus (L. half-tendinous). One of the dorsal muscles 

 of the thigh. 



Senso'rium (L. sentio, I perceive by the senses). The seat of 

 sensation. The nervous centre or centres to which sensory 

 impressions must be conveyed before they can be per- 

 ceived. 



Sen'sory (L. sentto, I perceive by the senses). Capable of 

 sensation. Applied to those nerves and nerve-fibres which 

 convey impulses resulting in sensation to a nerve-centre. 

 Also sometimes somewhat loosely employed in the sense 

 of afferent, to indicate nerve-fibres which convey impres- 

 sions of any kind to a nerve-centre. 



Se'pal. One of the leaflets forming the calyx of a flower. 



Se'piostare (L. sepia, the cuttle-fish). The "cuttle- bone," the 

 only representative of an endoskeleton in the cuttle-fishes. 



Sep'tula re'num (L. little partitions of the kidneys). The in- 

 ward prolongations of the cortical portion of the kidney. 



Sep'tum (L. sepio, I hedge in). A partition, as the septum 

 between the right and left sides of the heart 



Sep'tum lu'cidum (L. clear, bright partition). The partition 

 which separates from each other the lateral ventricles 

 of the brain. 



Sep'tum na'si ") (L. partition of the nose or nostrils). The 



Sep'tum na'rium ) partition which separates the nostrils. 



Sep'tum pectinifor'me (L. comb-like partition). The partition 

 between the corpora cavernosa of the penis. 



Sep'tum posti'cum (L. posterior partition). A partition which 

 divides the subarachnoid space on the dorsal surface of 

 the cord. 



Sep'tum scro'ti (I* partition of the scrotum). A partition in the 

 scrotum which separates the two testes. 



