873 



Fomnwn — an opening' or pore; sjiecifically the opening for 

 the pedicle in the pedicle valve of the Brachiopoda. 



Fossula — a groove in the calyx of a coral, usually due to 

 the abortion of a septnni. 



Fi'o/jc/— the foliaceous or leaf-like expansion of the skeleton 

 of Bryozoa and other organisms. 



Gemil spines — the posterioi- ])rolongations, or spines, of the 



free cheeks of Trilobites. 

 Gibbous — swollen or humped. 

 Glabella — the central, most prominent, portion of the Trilo- 



bite cephalon, l)ounded by the fixed cheeks. 

 Gonopolyp — the reproductive polyp of Hydrozoa. 



Hexacoralla — a class of corals l)uilt on the plan of six. 

 Hinge area — tlie flat area bordering the hinge line of many 



Brachiopods. 

 Hinge line — the line of articulation. 

 Hydrotheca — the cup enclosing the nutritive polyp in the- 



caphore Hydrozoa. 

 Hyponouie — the water tube, or s(piirting oi-gan, of squids, 



cuttlefish, and other Cephalopods. 

 Hypostoma — the underlip of the Trilobites, usually found 



detached. 



Imbricate — overlapping serially. 



Implantation — planting between, as a new plication sud- 

 denly appearing between two older ones. 



Inarticulate — not articulating by teeth and sockets; of 

 Brachiopoda. 



Incised — cut into. 



Infrabasals — the lower cycle of basal plates in the Crinoids 

 with dicyclic base. 



Intundib ulifovm — funnel-shaped. 



Inosculating — connecting, so as to have intercommunica- 

 tion. 



Interambulacral— between the ambulacra. 



