Z D 



peculiar in its own composition, 

 but from its being the area within 

 which the apparent motion of the 

 sun, moon, and all the great pla- 

 nets are confined. The centre of 

 the zodiac is the ecliptic, which is 

 inclined to the equinoctial at an 

 angle of about 23 28', intersecting 

 it at two opposite points, called 

 the equinoctial points. The zodiac 

 extends 9 on either side of the 

 ecliptic. 



ZODI'ACAL. Pertaining to the zodiac, 

 as the zodiacal constellations, &c. 



ZOI'SITE. | A mineral, thus named from 



ZOI'ZITE. ) Baron Yon Zois, its dis- 

 coverer. A variety of Epidote, of 

 a grey, brown, or yellowish colour. 

 Prof. Jameson constitutes zoisite a 

 species, which he divides into two 

 subspecies, namely, common zoisite 

 and friable zoisite: he adds, "it 

 would probably be an improvement 

 to arrange zoisite as a subspecies of 

 epidote." 



ZOO'LOGY. (from %ov, an animal, 

 and XoV/o?, discourse, Gr.) That 

 branch of natural history which 

 treats of animals, their habits, 

 structure, classification, &c. 



ZOO'LOGY FOSSIL. That division of 

 zoology which treats of fossil ani- 

 mals. The examination of the 

 fossil remains of a former state of 

 creation has demonstrated the ex- 

 istence of animals far surpassing in 

 magnitude those now living, and 

 brought to light many forms of 

 being which have nothing anala- 

 gous to them at present, and many 

 others which afford interesting con- 

 necting links between existing ge- 

 nera. 



ZOO'PHAGA. (from woi>, an animal, 

 and 0a<yeti/, to eat, Gr.) A tribe 

 of animals which attack and devour 

 living animals. The animals of this 

 tribe have three kinds of teeth, 

 namely, cutting teeth, canine teeth, 

 and grinders; their paws are armed 

 with claws ; their muzzle is often 

 set with whiskers, usually called 



[_ 469 ] ZOO 



smellers; their mammary organs 

 are dispersed ; their intestines are 

 less voluminous than those of her- 

 bivorous animals. 



ZOO'PHAGOTJS. Attacking and devour- 

 ing living animals. 



ZO'OPHYTE. (gwofora, from oW, 

 and 0vw, Gr. qua media sunt na- 

 tura inter animalia et plantas.) 

 Animal plants, corals, sponges, and 

 other aquatic animals which have 

 obtained the name from an opinion 

 formerly entertained that they were 

 intermediate between animals and 

 vegetables. In consequence of their 

 aggregation, which produces trunks 

 and expansions of various forms, 

 together with the simple nature of 

 their organization, and the radia- 

 ting disposition of their organs, 

 resembling the petals of flowers, 

 these animals owe their name of 

 zoophytes or animal plants. But 

 possessing the power of voluntary 

 motion, enjoying the sense of touch, 

 feeding on matters which they have 

 swallowed, and digesting these in 

 an internal cavity, they must, in 

 every point of view, be considered 

 to be animals. Many of the lowest 

 zoophytes, which have no digestive 

 sac, and no polypi, absorb their 

 whole nourishment by the surface 

 of their body, or by the parieties 

 of canals which traverse their in- 

 interior. Zoophytes present to the 

 physiologist the simplest indepen- 

 dent structures compatible with the 

 existence of animal life; the means 

 of their propagation and increase 

 are the first of a series of facts on 

 which a theory of generation must 

 rise. Zoophytes are either free in 

 the sea, or are attached for life 

 after a very early period of growth. 

 "We may compare," says Lyell, 

 " the operation of zoophytes in the 

 ocean to the effects produced on a 

 smaller scale upon the land by the 

 plants which generate peat. In 

 corals, the more durable materials 

 of the generation that has passed 



