Exuviation

The proce by which certain of the animal creation cast off their skins, or shells, and form a new one. Ex visceribus. [Lat.] From the vital part; the very e ence of the thing. Ex vo'to. [Lat.] After one's wishes; according to a vow. Ey, Ey'et, Ey'ot, n. [Probably from A. S. ig, an island.] A small island. (o.) See AIT. Eyafialla-Yokul, ( i - a - fe - al'la - yokool ,) a volcano of Iceland, about 15 m. S.E. of Mount Hecla. E'yas, E'yas-musket, (i'as,) n. [Fr. niais , probably from Lat. nidicus , a nestling, from nidus , a nest.] A young hawk just from the nest, and not able to prey for itself. partly of modified connective ti ue, which envelops and holds together the former. The choroid , which is the next tunic of the eye, consists of a thin and highly vas cular membrane, of which the internal surface is cov ered by a layer of black pigment cells. The principal use of the choroid is to absorb, by means of its pigment, those rays of light which pa through the transparent retina, and thus prevent their being again thrown upon the retina and interfere with the distinctne of the images there formed. Certain transparent refracting media are placed in front of the retina for the purpose of collecting together into one point the different diverging rays emitted by each point of the external body, and of giving them such directions that they shall fall on corresponding points of the retina, and thus produce an exact image of the object from which they proceed. Without this optical apparatus before the retina nothing distinctly could be perceived. These refracting media are the cornea, the aqueous humor, the crystalline lens, and the vitreous humor. The cornea is a dense, perfectly transparent substance, convex anteriorly, concave posteriorly, and composed of fibrous ti ues arranged in numerous distinct lamine. Behind the cornea is a space containing a thin watery fluid, the aqueous humor. This space is divided into two chambers, the anterior and the posterior, by a membranous partition, the iris , whose muscular fibres have a direction for the most part radiating from the circumference towards the central aperture, the pupil ; but as they plexities. - Act of sending out, or evolving. "Made rather by transmutation than extrication." Boyle. Extrin's ic, or Extrin's ical, a . [Fr. extrinsèque; Lat. extrinsecus.] External; outward; extraneous; for- eign; not belonging to a body. Extrinsicality, n. Externality. Extrinsically, adv . In a manner not e ential to the subject, or foreign thereto. Extro'itive, a . [Lat. extra , outside, and ire, to go.] Seeking things entirely objective. Extro pium, n. ( Surg .) See ENTROPIUM. Extrorse', or Extror's al, a. ( Bot .) Denoting the direction of bodies, from the axis to which they apper- tain; thus anthers, whose line of dehiscence is towards -Front; face. the petals, are said to be extrorse. Extroversion, n. [Lat. extra , outside, and versio , a turning.] ( Surg .) One of those malformations of the body in which a part is, as it were, turned wrong side outward.