20 



CHOUTEAU CORALS 



Right counter quadrant: Portion of thecarium 

 between counter septum and right alar sys- 

 tem when counter is orientated away from 

 observer. 

 Rootlet: Root-like prolongation near apex. 



Radicifornt process. 

 Root-like process*: Proximally directed prop 



generally confined to proximal portion. 

 Ruga*: 1 (Obsolete.) Longitudinal ridge on 

 epitheca not coinciding with septa. P^<'w^/o- 

 costa, Interseptal r-idge, Costa 2. 

 Ruga: 2 Encircling striation on epitheca 



coarser than transverse striation. 

 Rugose: Corals with metasepta inserted at 



four points. 

 Scales: Small plates attached in vertical rows 

 to septal grooves and Interseptal ridges. 

 Exothecal scales. 



Sclerenchyme: Calcareous material of skel- 

 eton. Stereoplasm, Stereome. 



Sclerocolumella : Axial structure consisting of 

 irregularly deposited calcareous material in 

 late stages. 



Sclerotheca: Inner wall formed by densely 

 packed ring of dissepiments. 



Scolecoid: Cylindrical corals whose direction 

 of growth Is Irregular. Geniculate In part. 



Secondary septa: Principal septa added later 

 than primary septa but before any possible 

 tertiary septa. Metasepta, In part. 



Secondary wall*: (Obsolete.) See Inner wall. 



Septal budding: Partitioning of parent calyx 

 into two to four subdivisions by curving of 

 primary septa. 



Septal cone: Hollow cones with apex (either 

 central or eccentric) directed proximally, 

 cone thinning distally. 



Septal fillet: Discontinuous septum with tra- 

 beculae fused to form band-like septa In 

 horizontal bands. 



Septal grating: Discontinuous septa with 

 superimposed comb-like unfused trabeculae. 



Septal groove: Longitudinal depression cor- 

 responding In position to septum. Septal 

 sulcus. 



Septal ridge: Very short vertical ridge on In- 

 side of epitheca at position of septum. 



Septal sulcus*: Longitudinal groove on theca, 

 corresponding to position of septum. Septal 

 groove. 



Septum: Longitudinal plate extending In- 

 wards from epitheca; may be acanthlne, 

 carlnate, thin, dilated, long, short, amplex- 

 oid, sinuous, retiform, perforate, continu- 

 ous, discontinuous. 



Shape stage: Portion of coral characterized 

 by recognizable difference in external form. 



Short septum: Extending only short distance 

 axially from periphery. Amplexoid septum 

 in part. 



Simple: Corals which lived singly, as opposed 

 to compound corals. Solitary. 



Siphonofossula: Deep fossula with down- 

 warped tabulae. 



Smooth: Character of theca. 



Solitary: Corals which lived singly, as op- 

 posed to compound corals. Simple. 



Spine: Outwardly directed extension on 

 theca. 



Splnulose striation*: See Septal ridge. 



Squamula: Degenerate tabula terminating In 

 free edge within lumen; may overlap other 

 squamulae (interlocking). 



Stereocolumella: Axial structure consisting of 

 stereoplasm deposited In late stages. 



Stereome: Calcareous secondary deposit upon 

 skeletal structures. Sclerenchyme, Stereo- 

 plasm. 



Stereoplasm: Calcareous secondary deposit 

 upon skeletal structures. Sclerenchyme, Ster- 

 eome. 



Stereotheca: Inner wall formed by addition 

 of stereoplasm to skeletal parts In ring 

 within thecarium. 



Stereozone: Portion of coralllte extensively 

 built up by stereoplasm. 



Stolon budding: Origination of new bud from 

 horizontal tube connecting neighboring 

 corallites ; all three units have connected 

 visceral cavities. 



Stolonal budding: Increase by sending out 

 creeping basal prolongations from which 

 new corallites arise. 



Straight: Used to modify designation of shape 



In simple corals. 

 Streptocolumella: Axial structure caused by 



twisting of ends of septa. Axial vortex. 

 Synapticula: Transverse conical or cylindrical 



bar between septa. 

 Tabella: Short arched tabula located axially, 



generally associated with lamellae. 

 Tabula: Transverse skeletal elements form- 

 ing floor of calyx at each successive stage; 

 commonly best developed In central region ; 

 may be complete or Incomplete. 

 Tabular budding: Origination of new calyx 

 from wall of parent but enveloped by tabula. 

 Tabularium: Axial zone of tabulae. 

 Tachygenesis: Acceleration of ontogenetic de- 

 velopment. 

 Talon: Arched lateral expansion near apex. 



Term not recommended. 



