GLOSSARY. 391 
Didymous, in pairs. 
Disc, the surface with the margin or the flat base of adherence. 
Dissepiment, a partition. 
Distal, opposed to anteal. 
Distichous, placed in two opposite rows. 
Divaricate, spreading out widely. 
Dredge, a drag-net for taking mollusca, zoophytes, etc. 
Echinated, set with spines, or bristled like a hedgehog. 
Edentulous, toothless. 
Elliptical, oval, but having the longitudinal diameter twice the 
length of the transverse. 
Emarginate, notched on the margin. 
Ensiform, shaped like a sword. 
Epidermis, the outer covering, or scarf-skin. 
Frose, irregularly notched, as if gnawed. 
Everted, turned outward. 
Faicate, bent like a scythe. 
Fasciculate, tufted and level-topped. 
Fauna, the animals peculiar to any country. 
Filiform, thread-shaped. 
Fimbriated, fringed. 
Fissure, a little cleft. 
Fistular, like a pipe. 
Flabelliform, fan-shaped. 
Flexwous, bending, gently winding. 
