CYL 



C YP 



kingdom of animals, or Mollusca, com- 

 prising animals distinguished by the 

 high development of the cerebral ganglia, 

 and their circular distribution around the 

 oesophagus. These are the Heterogan- 

 gliata of Owen . 



CYCLO-NEURA {kvkXo^, a circle, vey- 

 poi/, a nerve). A term applied by Dr. 

 Grant to the first sub-kingdom of ani- 

 mals, or Radiata, as expressive not only 

 of the common circular form of the 

 nervous axis in this division, but also of 

 its rudimental state of simple ^/aiwew/5. 



CY'CLOID [kvkXo^, a circle, eidoc, 

 likeness). A geometrical transcendental 

 curve, described by a point in the circum- 

 ference of a circle, which rolls along a 

 plane until it has completed a revolu- 

 tion. Thus the nail on the felly of a 

 wheel moves in a cycloid, as the carriage 

 goes along, and as the wheel itself both 

 turns round its axle and is carried along 

 the ground. 



When the tracing point is placed with- 

 out the circle, the curve has its base 

 shortened, and is called the curtate or 

 contracted cycloid. If the point is within 

 the circumference, the curve is called 

 the prolate or inflected cycloid. 



CYCLO'SIS [kvkXo^, a circle). A cir- 

 cular movement of the globular particles 

 of the sap, as observed in the cells of 

 Chara and Nitella, and in the jointed 

 hairs projecting from the cuticle of 

 several other plants. A similar motion 

 has been recently found by Mr. Lister to 

 exist in a great number of Polypiferous 

 Zoophytes. 



CYCLO'STOMI {kvkXo'!, a circle, <Tr6- 

 fia, a mouth). An order of Chondropte- 

 rygious or Cartilaginous Fishes, having a 

 round fleshy lip, by which they adhere to 

 their prey, obtaining their food by suction, 

 as in the lamprey. The lip is supported 

 by a cartilaginous ring, formed by the 

 union of the jaw-bones. In fishes of this 

 order the vertebrated structure is found 

 in \i& lowest form. 



CYGNUS. The Swan ; a northern con- 

 stellation containing eighty-one stars, the 

 principal of which is Dereb Adige. 



CY'LINDER {KvKivbpo^, a cylinder). 

 A geometrical solid, with a circular base, 

 described by the revolution of a right- 

 angled parallelogram about one of its 

 sides, which remains fixed. It is a cir- 

 cular prism, as a cone is a circular pyra- 

 mid. The axis of a cylinder is the fixed 

 straight line about which the parallelo- 

 gram revolves. When the base is ellip- 

 tical, the solid is a cylindroid ; when the 

 99 



sides are perpendicular to the base, it is 

 aright cylinder or cylindroid; in other 

 cases it is an oblique cylinder. 



CYLINDRE'NCHYMA {Kv\tv6po<:, a 

 cylinder, eyx^iJ-a, infusion). A designa- 

 tion given by Morren to the cylindrical 

 variety of the parenchyma of plants. 



CYM'BIFORM (cymda, a boat, forma, 

 likeness). Navicular, or boat-shaped, as 

 applied to the glumes of certain grasses, 

 and synonymous with carinate. 



CYME. A form of inflorescence re- 

 sembling an umbel and a corymb, but 

 with a centrifugal expansion, indicated 

 by the presence of a solitary flower in 

 the axis of the dichotomous ramifications. 



CY'MOPHANE. The designation 

 given by Haiiy to chrysoberyl. 



CY'MOSE. Resembling a cyme,- as 

 applied to inflorescences and leafy 

 branches. 



CYNARA'CEiE. A division of the 

 Compositce, named from the genus cy- 

 nara, and comprising plants charac- 

 terized by intense bitterness, which de- 

 pends upon the mixture of extractive 

 with a gum which is sometimes yielded 

 in great abundance. 



CYNA'RRHODON. In Botany, an 

 aggregate fruit, consisting of distinct 

 ovaries ; the pericarps are hard, inde- 

 hiscent, enclosed within the fleshy tube 

 of a calyx, as in rose, calycanthus, &c. 

 The term is a Greek compound for dog-rose. 

 CYNITIDiE (cynips, the gall-fly). 

 The Gall-flies ; a family of the entomo- 

 phagous Terebrantia, which, by means 

 of their ovipositor, form tumors on plants, 

 commonly termed galls, nut-galls, or gall 

 apples. 



CYPERA'CE^. The Sedge tribe of 

 Monocotyledonous plants, named from 

 the genus cyperus. These plants re- 

 semble grasses in appearance, but have a 

 solid and angular stem, without a dia- 

 phragm at the articulations ; the flowers 

 grow in the axil of a single bract ; and the 

 cotyledonar extremity of the embryo is 

 enclosed within the albumen. See Gra- 

 minacecB. 



CYPHE'LL^ {KvipeWa, the hollows of 

 the ears). Pale tubercle-like spots on the 

 under surface of the thallus of lichens, as 

 in sticta. 



CY'PHER or CIPHER. In common 

 language, to cypher is to calculate ; and 

 to write in cyphers is to write in secret or 

 unknown characters, such as were the 

 Arabic numerals when first introduced 

 Into Europe. 



CYPRiE'lDiE. The Cowries or Por- 

 F2 



