378 



Septum — a partition; in corals, the radiating calcareous 

 plates; in Cephalo])0(ls, the transverse partition between 

 the chambers. 



Setifeir>us — biistle-bea ring. 



Siiiinoid — curved like the Greek letter ? (signia). 



Sinuate — wavy, winding. 



Sinus — an impression in the surface or margin of a shell. 



Siplional funnel — the siphonal projection from the septum 

 of a Cephalopod shell. 



Siphonnl lobe — the lobe, in the suture of an Ammonoid shell, 

 coiTesponding in position to the siphuncle. 



Siphuncle — the tubular canal, passing through the air- 

 chambers in the shells of Cephalopods. 



Spatulcite — shaped like a spatula; spoon-shaped. 



Spin ulose — spine bearing. 



Sub — in composition indicates a low degree : sub-angular — 

 rather angular; sub-carinate — somewhat toothed, etc. 



Sulcus — a f u ri-o w . 



Suture — in Cephalopods — the line of juncture between shell 

 and septum, seen on breaking away the former; in 

 Gastropods — the external line of juncture between the 

 several whorls ; in Trilobites — the dividing line between 

 fixed and free cheeks, commonly called facial sutuiv ; 

 in Crinoids — the line of juncture between adjacent 

 plates. 



Tabuhe — the transverse, continuous partitions or floors in 



corals, etc. 

 Tegnien — the vault or cover of the calyx in Oinoids. 

 Terebratuloid — like the recent genus Terebratula. 

 Test—^\\Q\\. 



Tetranieral — on the plan of four. 

 Theca — the proper wall of the individual corals. 

 Thorax— the central part of the body of the Trilobites. 

 Trabecule — projecting bars. 

 Trigonal — three-angled . 

 Trihedral — with three erpial faces. 



