tegmina's Usage Examples:

are either incorporated in, or pressed below, the tegmen by interambulacrals; all thecal plates united by suture, somewhat loose in the earliest forms, but speedily becoming close, and producing a rigid theca; mouth and tegminal food-grooves closed; arms pinnulate.

These either are close to the mouth or are removed from it upon a series of ambulacral or subambulacral plates not derived immediately from thecal plates, or are separated from the oral centre by hypothecal passages passing beneath tegminal plates.

- Monocyclica in which the dorsal cup is confined to the patina and occasional intercalated anals;: such ambulacrals or interambulacrals as enter the tegmen remain supra-tegminal and not rigidly united.

Tegmen flexible, with distinct ambulacrals and numerous small interambulacrals; mouth and food-grooves remain supra-tegminal and open.

"- Monocyclica in which the dorsal cup is confined to the patina and occasional intercalated anals;: such ambulacrals or interambulacrals as enter the tegmen remain supra-tegminal and not rigidly united.