Cuspidate

Furnished with small pointed eminences or " cusps."

Cuticle

(Lat. cuticula, dim. of cutis, skin). The pellicle which forms the outer layer of the body amongst the Infusoria. The outer layer of the integument generally.

Cutis

(Lat. skin). The inferior vascular layer of the integument, often called the cutis vera, the corium, or the dermis.

Cycloid

(Gr. kuklos, a circle; eidos, form). Applied to those scales of fishes which have a regularly circular or elliptical outline with an even margin.

Cyclostomi

(Gr. kuklos; and stoma, mouth). Sometimes used to designate the Hag-fishes and Lampreys, forming the order Marsipobranchii.

Cyst

(Gr. kustis, a bladder or bag). A sac or vesicle.

Cystica

The embryonic forms (scolices) of certain intestinal worms (Tapeworms), which were described as a distinct order, until their true nature was discovered.

Cystoidea

(Gr. kustis, a bladder; and eidos, form). An extinct order of Echinodermata.

Decapoda

(Gr. deka, ten ; podes, feet). The division of Crustacea which have ten ambulatory feet; also the family of Cuttle-fishes, in which there are ten arms or cephalic processes.

Deciduous

(Lat. decido, I fall off). Applied to parts which fall off or are shed during the life of the animal.

Decollated

(Lat. decollo, I behead). Applied to univalve shells, the apex of which falls off in the course of growth.

Deinocerata or Dinocerata

(Gr. deinos, terrible; keras, horn). An extinct order of Tertiary Mammals.

Detnosauria or Dinosauria

(Gr. deinos, terrible; saura, lizard). An extinct order of Reptiles.

Dendriform, Dendritic, Dendroid

(Gr. dendron, a tree). Branched like a tree, arborescent.

Dentirostres

(Lat. dens, a tooth ; rostrum, a beak). The group of Perching Birds in which the upper mandible of the beak has its lower margin toothed.

Derma or Dermis

(See Cutis.)

Dermal

(Gr. derma, skin). Belonging to the integument.

Dermosclerites

(Gr. derma, skin ; skleros, hard). Masses of spicules which occur in the tissues of some of the Alcyonaria (Actinozoa).

DESMIDIAE

Minute fresh-water plants, of a green colour, without a siliceous epidermis.

Deuterozooids

(Gr. deuteros, second; zoon, animal; eidos, form). The zooids which are produced by gemmation from zooids.

Dextral

(Lat. dextra, the right hand). Right-handed; applied to the direction of the spiral in the greater number of univalve shells.

Diaphragm

(Gr. diaphrogma, a partition). The " midriff," or the muscle which in Mammalia forms a partition between the cavities of the thorax and abdomen.

Diastema

(Gr. dia, apart; histemi, I place). A gap or interval, especially between teeth.