798 GLOSSARY. 



ENDOSARC (Gr. endon; and sarx, flesh). The inner molecular layer of sarcode 



in the Amoeba, and other allied Rhizopods. 

 ENDOSKELETON (Gr. endon; and skeletos, dry). The internal hard structures, 



such as "bones, which serve for the attachment of muscles, or the protection 



of organs, and which are not a mere hardening of the integument. 

 ENSIFORM (Lat. ensis, a sword ; forma, shape). Sword-shaped. 

 ENTOMOPHAGA (Gr. entoma, insects; phago, I eat). A section of the Mar- 



supialia. 

 ENTOMOSTRACA (Gr. entoma, insects ; ostrakon, a shell). Literally, shelled 



insects applied to a division of Crustacea. 

 ENTOZOA (Gr. entos, within ; zob'n, animal). Animals which are parasitic in 



the interior of other animals. 

 EOCENE (Gr. eos, dawn ; kainos, new or recent). The lowest division of the 



Tertiary rocks, in which species of existing shells are to a small extent re- 

 presented. 

 EPHIPPIUM (Gr. ephippion; Lat. ephippium, saddle). A receptacle on the 



back of the Daphnia, in which the winter eggs are deposited. 

 EPIDERMIS (Gr. epi, upon ; derma, the true skin). The outer non-vascular 



layer of tne skin, often called the scarf-skin or cuticle. 

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



of the somite of a Crustacean. 

 EPIPODIA (Gr. 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 



thecse in some Corals externally. 

 EPIZOA (Gr. epi, upon ; zob'n, animal). Animals which are parasitic upon 



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



parasitic upon fishes. 



EQUILATERAL (Lat. cequus, equal ; latus, side). Having its sides equal. Usu- 

 ally 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. 

 EQUIVALVE (Lat. cequus, equal ; valvce, folding-doors). Applied to shells 



which are composed of two equal pieces or valves. 

 ERRANTIA (Lat. erro, I wander). An order of Annelida, often called Nereidea, 



distinguished by their great locomotive powers. 

 EURYPTERIDA (Gr. eurus, broad; pteron, 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 ; skeletos, dry). The external skeleton, which 



is constituted by a hardening 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. 



FEMUR. The thigh-bone, intervening between the pelvis and the bones of the 

 leg proper (tibia and^ifotZa). 



FIBULA (Lat. a brooch). The outermost of the two bones of the leg in the 

 higher Vertebrata ; corresponding to the ulna of the fore-arm. 



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



FISSILINGUIA (Lat. findo, I cleave ; lingua, tongue). A division of Lacertilia, 

 with bifid tongues. 



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

 division. 



