GLOSSARY. 297 



EPIMERA (Gr. epi, upon ; meron, thigh). The lateral pieces of the dorsal arc 



of the somite of a Crustacean, 

 EPIPODIA (G-r. epi, upon; pous, the foot). Muscular lobes developed from 



the lateral and upper surfaces of the ' foot' of some Molluscs. 

 EPIPODITE (Gr. epi, upon ; pous, foot). A process developed upon the basal 



joint, or ' protopodite/ of some of the limbs of certain Crustacea. 

 EPISTERNA (Gr. epi, upon; sternon, the breast-bone). The lateral pieces of 



the inferior, or ventral, arc of the somite of a Crustacean. 

 EPISTOME (Gr. epi; and stoma, mouth). A valve-like organ which arches 



over the mouth in certain of the Polyzoa. 

 EPITHECA (Gr. epi; and theke, a sheath). A continuous layer surrounding 



the thecae in some Corals, and being the external indications of tabulae. 

 EPIZOA (Gr. epi, upon ; zoon, animal). Animals which are parasitic upon 



other animals. In a restricted sense, a division of Crustacea which are 



parasitic upon fishes. 

 EQUILATERAL (Lat. csquus, equal ; latus, side). Having its sides equal. 



Usually applied to the shells of the Brachiopoda. When applied to the 



spiral shells of the Foraminifera, it means that all the convolutions of the 



shell lie in the same plane. 

 ERRANTIA (Lat. crro. I wander). An order of Annelida, often called Ne~ 



reidea, distinguished by their great locomotive powers. 

 EURYPTERIDA (Gr. eurus, broad ; ptcron, wing). An extinct sub-order of 



Crustacea. 

 EXOPODITE (Gr. exo, outside ; pous, foot). The outer of the two secondary 



joints into which the typical limb of a Crustacean is divided. 

 EXOSKELETON (Gr. exo, outside ; skeleton, dry). The external skeleton, which 



is constituted by a hardening of the outer layer of the integument, and 



is often called a ' dermoskeleton.' 



FASCICULATED (Lat. fasciculus, a bundle). Arranged in bundles. 



FAUNA (Lat. Fauni, the rural deities of the Romans). The general assem- 

 blage of the animals of any region or district. 



FILIFORM (Lat. filum, a thread ; forma, shape). Thread- shaped. 



FISSION (Lat. findo, I cleave). Multiplication by means of a process of 

 self-division. 



FISSIPAROUS (L&t.findo ; and pario, I produce). Giving origin to fresh 

 structures by a process of fission. 



FLAGELLUM (Lat. for whip). The lash-like appendage exhibited by many 

 Infusoria, which are, therefore, said to be ' flagellate.' 



FLORA (Lat. Flora, the goddess of flowers). The general assemblage of 

 the plants of any region or district. 



FOOT-JAWS. The limbs of Crustacea, which are modified to subserve mas- 

 tication. 



FOOT-SECRETION. The term applied by Mr. Dana to the sclerobasic coral- 

 lum of certain Actinozoa. 



FOOT-TUBERCLES. The unarticulated appendages of the Annelida, often 

 called parapodia. 



FORAMINIFERA (Lat. foramen, an aperture ; fero, I carry). An order of 

 Protozoa, usually characterised by the possession of a shell perforated by 

 numerous pseudopodial apertures. 



FUSIFORM (Lat. fusiis, a spindle ; and forma, shape). Spindle-shaped, or 

 pointed at both ends. 



GANGLION (Gr. gagglion, a knot). A mass of nervous matter, giving origin 

 to nerve-fibres. 



