'>• t/if iii, a of ii /<• nil in us, Hfit •/}• ,i tt-nt fo II I-NKV \V. II A GLOSSARY OF BIOLOGICAL, ANATOMICAL, AND PHYSIOLOGICAL TERMS. A GLOSSARY GF BIOLOGICAL, ANATOMICAL, AND PHYSIOLOGICAL TERMS. THOMAS DUNMAN, Lecturer on Physiology at the Birkbcck Institution, and Physical Science Lecturer at the Working Men's College. NEW YORK: D. APF COMPANY, AD WAY. 1879. PREFACE. EXPERIENCE both as a student and as a teacher having con- vinced me of the want of a Glossary of the numerous technical terms employed in the sciences of Anatomy, Physiology, and General Biology, I have been induced to prepare the present volume. In it is attempted to place before the student the pronuncia- tion, derivation, and definition of all those terms which are usually employed in that department of Biological science which treats of animal life, as set forth in such standard text- books as those of Huxley, Carpenter, Foster, Flower, and others. With the Botanical side of Biology but little has been attempted, only such terms having been included as are employed in Elementary General Biology as treated in the introductory text-book of Huxley and Martin, the object being rather to supply a want than to supplement existing works. Of Pathological terms only such have been included as are usually employed in the illustration of Physiological facts. In order to conduce to correct pronunciation, the accented syllable in each word is marked, and where necessary the Vi PREFACE. usual vowel signs have been employed; the mark " over a vowel signifying that it is to be pronounced short, and the mark " signifying that the vowel over which it is placed is long. Where a letter is silent in pronunciation, it is printed in italics. I have ventured to print the Greek roots in English cha- racters, choosing rather to run the risk of offending the sus- ceptibilities of the classical scholar, than to endanger the perfect clearness of the work to those to whom the Greek characters are not familiar. The definitions, while concise, will, it is hoped, be found sufficiently full, and are in all cases given in their most modern acceptance. Compiled at the request, and, primarily, for the benefit of my own students, this Glossary will, I hope, be found useful to all those who are preparing for the examinations of the Science and Art Department and other examining bodies, and especially to that large and deserving band of self-taught students to whom I shall be pleased to learn that it has been of service. THOMAS DUNMAN. LONDON, August, 1878. A GLOSSARY OF BIOLOGICAL, ANATOMICAL, AND PHYSIOLOGICAL TERMS. A. Abdo'men (L. abdere, to conceal).— In the Vertebrata, the posterior part of the cavity of the trunk, which contains the principal viscera ; in some of the Invertebrata, the hinder part of the body. Abdomina'lia. — A subdivision of the Crustacea, the members of which have appendages on the abdomen, but none on the thorax. Abducen'tes (L. ab, away from ; ducens, leading). — The name given to the sixth pair of nerves which supplies the ex- ternal rectus muscle of each eye, by which muscle the eyeball is rotated outwards, or away from the middle line. Abduc'tion (L. abduco, I draw away). — The drawing away of a limb from the middle line. Abduc'tor ter'tii interno'dii secun'di dl'giti (L. abductor of the third internode of the second digit). — A muscle found in both manus and pes in Hylobates (one of the Anthropo- morpha), which is not at present known in any other mammal. Abioge'nesis (Gr. a, not ; bios, life ; gennesis, birth). — The pro- duction of living from not-living matter. Spontaneous generation. Abo'masum (L. ab, away from, and omasum).— The fourth stomach of a ruminant, which leads from the third stomach or omasum. Abo'ral (L. ab, away from ; os, oris, the mouth). — The opposite face in a star-fish to that which contains the mouth. Acale'phae (Gr. akalephe, a nettle). — The jelly-fishes or sea nettles. 2 GLOSSARY. Acanthoc§'phala (Gr. akantha, a thorn ; kephale, the head). — A group of parasitic Invertebrata having a number of recurved hooks on the proboscis. Acantho didae (Gr. akantlwdes, thorny). — A sub-order of Ganoid fishes. Acanthd'pteri (Gr. akantha, a thorn; ptcron, a wing or fin). — A group of Teleostean fishes having spiny fins. Acari'na (Gr. akdri, a. mite). — A group of Arthropods which includes the mites and ticks. Accesso'rius ad flio-costalem (L. accessory to the ilio-costah's). — One of the dorsal muscles of the trunk. Acci'pitres (L. acclplter, a hawk). — In the old classification of birds, the order which included the birds of prey. Acephalous (Gr. a, without; kephale, the head). — Without a distinct head. Acer vulus cgr'gbri (L. acervulus, a little heap ; cerebrum, the brain). — A mass of gritty matter contained in the pineal gland. Aceta bulum (L. a vessel for holding vinegar). — The cavity in the innominate bone into which the femur articulates. Also applied to the suckers 'with which the cephalic processes of some Cephalopoda are provided. Ach6 tidae (Gr. achetes, a grasshopper). — The crickets. Achla'mydate (Gr. a, not ; ehlamys, chlamydos, a cloak, mantle)- — A term applied to those Branchiogasteropods which are destitute of a mantle. Aciculum (L. diminutive of dcus, a needle). — A sharp pointed process carried by the parapodiaof the polychoete Annelida. Acine'tae (Gr. akinetos, immoveable). — A group of the Infusoria, the members of which -in the adult stage are non-locomo- tive. Acine'tifonn. — A term applied to the embryo Infusorians, which resemble the Acineta. A'clni (L. drfnus, a grape). — The small granulations composing the substance of some glands. Acotyle'donous (Gr. a, not ; kotyledon, a cup-shaped hollow).— Applied to cryptogamic plants whose spores have no cotyledons or seed-leaves. Acri'didae (Gr. akris, akridos, a grasshopper) . — The grasshopper tribe of insects. A'crodont (Gr. akron, the summit ; odous, odontos, a tooth). — Having the teeth attached by their bases to the summit of the parapet of the jaw, as in some of the Lacertilia. GLOSSARY. 3 A'crogen (Gr. akron, the summit ; gennao, I produce). — A plant, the growth of which takes place at its summit. Acro'mion (Gr. akron, the summit ; omos, a shoulder). — The process of the scapula which forms the summit of the shoulder. Actinozo'a (Gr. aktis, a ray ; zoon, an animal). — A division of the Coelenterata. Adambula'cral ossicles (L. ad, to ; ambulacrum, a walk shaded with trees ; ossicle, a little bone). — In the star-fishes, the small ossicles against which the ambulacral ossicles abut, and which lie at the sides of the groove which the ambula- cral ossicles bound superiorly. Adduc'tion (L. ad, to; duco, I lead). — The bringing of a limb to the middle line ; the reverse process to abduction. Adduc'tor. — A muscle, the contraction of which brings a limb to another or towards the middle line. In the Lamelli- branchiata, the muscles which close the valves of the shell _ are termed adductors. A'denoid ( Gr. aden, a gland ; eidos, form) . — Glandular ; applied to a special variety of connective tissue found in glands. A'dipose (L. ddeps, fat). — Fatty. Ad'nate (L. ad, to; natus, born). — A term applied to the stipules of plants which adhere to the petiole. Adre'nal (L. ad, to ; renes, the kidneys). — A name given to two glandular bodies connected with the kidneys. Adventi'tia capilla'ris (L. adventicius, foreign, strange; capillus, a hair). — A continuous covering which some capillaries possess, and which is derived from the surrounding con- nective tissue. JEsthe'sodic (Gr. aisthesis, sense, perception). — Conveying sensor)' impulses ; sensitive. JEtio'logy (Gr. aitiologia, the giving an account). — The branch of Biology which treats of the origin and development of organic beings. Aetomor'phae (Gr. aetos, an eagle ; morphe, form). — The birds of prey. Afferent (L. ad, to ; fero, I carry). — Carrying to, as an afferent nerve which conveys impulses to a nerve centre. Aga'mic (Gr. a, not ; games, marriage). — Applied to ova which germinate without being impregnated. Agamoge'nesis (Gr. a, not ; gamos, marriage ; gennesis, a beginning) . — Non-sexual reproduction. Aglos'sa (Gr. a , not ; glossa, a tongue). — A group of the Am- phibia in which a tongue is not developed. Aglyphodo'ntia (Gr. a, not ; glupho, I carve ; odous, odontos, a tooth). — A division of the Ophidia which have none of the maxillary teeth grooved. Ag'minated (L. agmen, a troup). — Grouped together; as the agminated glands of Peyer in the small intestine. Ailnroi'dea (Gr. aiiouros, a cat). — A group of the Carnivora which includes the cats, civets, and hyaenas. Ala vespertilio'nis (L. the wing of the bat). — The name applied to that part of the womb between the Fallopian tube and the ovary, fromits resemblance. Alae (L. a/a, a wing). — The lateral petals of such a flower as that of the pea or bean. Also applied to winglike pro- cesses of bone or muscle, as the alae of the diaphragm and of the sphenoid bone. Alary (L. a/a, a wing). — Applied to certain muscles attached in pairs to the walls of the pericardial chamber inserted into the hypodermis in some Insecta. Albu'men (L. albus, white). — A proteid animal substance of which the white of an egg may be taken as an example. Vegetable albumen is a similar substance found in many seeds between the embryo and the integuments. Albnr'num. — The young wood of an exogenous stem. Alectromor'phse (Gr. alector, a cock ; morphc, form). — The fowls. Al'gse (L. algor, coldness, or alligo, to entangle). — The sea- weeds and similar plants. Alimen'tary canal (L. aliment 'urn, nourishment). — The di- gestive cavity from the mouth to the anus. Alimenta'tion (L. alimentum, nourishment). — The taking of nourishment into the system. Alina sal pro'cess (L. a/a, a wing ; nastts, the nose). — A pro- cess surrounding each nasal aperture in the chondro- cranium of the frog. Alisphe'noid (L. a/a, a wing ; os sphenoidis, the sphenoid bone). — A bone of the skull which is represented in human anatomy by the great wing of the sphenoid bone. Allan'tois (Gr. al/as, a sausage). — An outgrowth from the hinder part of the embryonic alimentary canal in mammals, birds, and reptiles, which performs the part of a respiratory organ during part of foetal life. Alligato'ricUe.— The alligator group of reptiles. GLOSSARY. 5 Alve'olns (L. alveolus, a little hollow). — A small depression ; the socket of a tooth. Also the name given to each of the five pieces of which the oral skeleton is composed in the Echinidea. The ultimate saccules of a racemose gland. Ambula'cra (L. ambulacrum, a garden walk). — The spaces in the tests of sea-urchins and star-fishes, containing the apertures through which the " tube feet " are protruded. Ambnla'cral. — Relating to the ambulacra, as the ambulacral vessels. Ambula'cral ossicles (L. ambulacrum, a garden walk ; ossiculum, a little bone). — In the star-fishes, the ossicles which bound the sides and roof of the ambulacral grooves. Am'bulatory (L. ambuldre, to walk). — Applied to the appen- dages of Crustacea which are used in walking. Ameta'bola (Gr. a, not; metabole, change). — The insects which do not undergo metamorphosis. Ami'adae. — A sub-order of Ganoid fishes. Am'monite (so called from their resembling the horns on the sta- tues of Jupiter- Ammon). — A group of extinct Cephalopods. Am'nion (Gr. amnos, a lamb). — One of the appendages of the foetus in mammals and birds. Amoe'ba (Gr. ameibo, I change). — A genus of the Rhizopoda, the members of which constantly change their shape. - Amce'boid (Gr. ameibo, I change). — Like an amoeba. Amphiarthro'sis (Gr. amphi, both ; arthron, an articulation). — An articulation of bones partaking of the character both of a diarthrosis or moveable joint, and a synarthrosis or immoveable joint. Amphibia (Gr. amphi, both; bios, life). — A division of the Vertebrata adapted for breathing in water when young, and in air when mature. Ampblcce'lus (Gr. amphi, both; koilos, hollow). — Applied to vertebrae which are concave at both ends. Amphidiarthro'sis (Gr. amphi, both; diarthrosis, an articulation). — A term applied to such an articulation as that of the lower jaw with the temporal bone, because it partakes of the nature of a hinge-joint, and, at the same time, admits of a movement from side to side. Amphidis'cus (Gr. amphi, both ; diskos, a disc or quoit). — A siliceous body resembling two cogged wheels connected by an axle, found in some sponges. Amphimor'phae (Gr. amphi, both ; morphe, form). — A group of birds which comprises the flamingoes. 6 GLOSSARY. Amphiox'us (Gr. ampin, both ; oxus, sharp, pointed). — The lowest vertebrate animal. Its body is pointed at both ends. Amphi poda (Gr. amphi, both; pous, podos, a foot). — A divi- sion of the Crustacea. Amphirhi'na (Gr. amphi, both ; rhis, rhinos, the nose). — Applied by Haeckel to the Elasmobranch fishes, because the nasal sac is double. Amphi sbae'uoida (Gr. amp/it's, both ways ; baino, I walk). — A group of the Laccrtilia. Ampulla (L. ampullor, I swell out).— The dilated extremities of the semicircular canals of the ear. Amygdalae (Gr. amugdale, an almond). — Two rounded lobes in the cerebellum. Amyla'ceons (Gr. amylon, starch).— Starch-like. Of or belong- ing to starch. Am'yloid (Gr. amylon, starch ; e'ulos, form). — Of the chemical nature of starch. Amyloly'tic (Gr. amylon, starch ; luo, I loose). — Having the power of converting starch into dextrin and grape-sugar. Anacan'thini (Gr. anakanthos, without thorns). — A group of Teleostean fishes. Anae'mia (Gr. an, not ; aima, blood). — A pathological term signifying a deficiency of blood ; the condition of the body after a great loss of blood. Anoesthe sia (Gr. anaisthetos, senseless). — Loss of sensation. AnapS'physis (Gr. ana, upon ; apophuo, I grow). — The lower of two accessory processes which sometimes appear on the neural arches of the lumbar vertebrae. Anap'tychi (Gr. anaptyche, unfolding). — Heart-shaped plates of shelly substance found in some Goniatites and Ammo- nites. AnarthrS'poda (Gr. a, not ; arthros, a joint ; potts, podos, a foot). — A division of the Annulosa, the members of which are destitute of jointed limbs. Anas'tomose (Gr. ana, through ; stoma, a mouth). — To open into each other (as do veins and arteries), so as to form a network. Ana'tomy (Gr. ana, up ; temno, I cut). — The science which treats of the structure of organisms as determined by their dis- section. Anchylo'sis (Gr. ankule, a thong or clasp). — The union of two or more separate bones so as to form only one bone. GLOSSARY. 7 Anco'neus (Gr. ankon, the elbow). — A name given to muscles placed mainly below the elbow and fore-arm. An'drophore (Gr. aner, andros, a man; phoreo, I bear). — The branches of the gonoblastidium of some Siphonophora which bear the male gonophores. An'eurism (Gr. aneuruno^ I enlarge). — A tumour filled with blood arising from the rupture, wounding, or dilatation of an artery. Anfractuo'sities (L. anfradus, a winding).— The furrows or sulci which divide the convolutions of the brain. Angeio'logy (Gr. angeion, a vessel; logos, discourse). — The department of Anatomy which comprises a description of the blood-vessels and absorbents. An'gular (L. angulus, a corner). — A bone of the mandible in some Vertebrata. Ang'ulo-sple'nial (L. angulus, a corner ; splenium, a splint). — One of the bones of the mandible in some vertebrate skulls. An'kylose (see Anchylose). Annelida (L.annulits, a ring). — A division of the Anarthropoda which embraces the earth-worm, leech, &c. Annula'ris (L. annulus, a ring). — The fourth digit of the manus, which in man is the "ring-finger." Annuloi'da (L. annulus, a ring). — A division of the Invertebrata, formerly including the Echinodermata and the Scolecida, but now used by Huxley for a series which embraces the Annelida and Trichoscolices/ Annulo'sa (L. annulus > a ring). — A division of the Invertebrata which includes the Arthropoda and Anarthropoda. An'nulus (L. a ring). — Applied to a thin ring of chitine which encircles the mantle of the Tetrabranchiata, and into which the shell muscles are inserted. Also to the cellular ring which lines the sporangium of a fern. An'nulus ovalis (L. oval ring). — The border which bounds the fossa ovalis of the septum between the auricles of the heart. Anodon'ta (Gr. an, not ; odous, odontos, a tooth). — The fresh- water mussels, which are bivalve molluscs, having valves which are destitute of teeth. Anomu'ra (Gr. anomos, irregular; cura, a tail). — A tribe of Decapod Crustacea, of which the hermit crab is a type. Anoplothe'ridse (Gr. anoplos, unarmed; ther, a beast). — A family of extinct mammals belonging to the eocene and miocene epochs. S GLOSSARY. Anor'thoscope (Gr. anortho, I set straight again ; skopeo, I be hold). — An instrument so constructed, that distorted images drawn on cards for the purpose, on being placed in it, and whirled rapidly round, are seen restored to their just proportions. Antambula'cral face (Gr. anti, opposite).— In the star-fish, that face on which there are no ambulacra. Ante-bra'chium (L. ante, before; brachium, the arm from the elbow to the wrist). — The fore-arm. Antefur'ca (L. ante, before; furca, a fork). — The anterior forked projections from the sternal wall in each somite of a cockroach. Anten'na (L. the yard-arm of a ship). — A jointed appendage of the head in Insecta, Crustacea, and Myriapoda. Anten'nnle (L. dim. of antenna). — The shorter pair of antcnnce in the Crustacea. Ante'rior (L. ante, before). — In Comparative Anatomy, towards the head In Human Anatomy often employed in the sense of ventral. An'ther (Gr. anthos, a flower).— In plants, the sac of the stamen which contains the pollen. Antherf dium (Gr. anthos, a. flower ; eidos, form). — The repro- ductive organs of ferns and other cryptogamic plants which contain the male reproductive elements. Anthe'rozoids (Gr. anthos, a flower; zoon, an animal). — The vibratile filaments in cryptogamic plants which are the homologues of the spermatozoa of animals. Anthro'pidae (Gr. anthrdpos, a man). — The genus man. An'thropomor'pha (Gr. anthrdpos, a man ; morphe, form). — The man-like apes. Antihe'lix (Gr. anti, opposite). — The curved ridge of the external ear within the helix. Antitra'gus (Gr. anti, opposite). — A small elevation of the external ear opposite the tragus. Antitrochan'ter (Gr. anti, opposite). — The articular surface on the ilium of birds on which the great trochanter of the femur plays. An'tram pylo'ri (L. cave of the pylorus). — A depression near the pyloric end of the human stomach. Anu'ra (Gr. a, not; oura, a tail). — A group of the Amphibia, comprising the frogs and toads, the members of which are destitute of tails. A'nus (L. a vent). — The external opening of the large intestine. GLOSSARY. 9 Aor'ta (perhaps fiom Or. aeiro, I take up, suspend, or carry). — • The main artery which springs from and suspends the heart. Apha'sia (Gr. a, not; phasis, speech). — Loss of the mental faculty of speech as distinguished from paralysis of the organs concerned in speech. Apnce'a (Gr. a, not ; pneo, I breathe). — A condition in which, owing to an abnormally large supply of oxygen to the blood, the respiratory movements are temporarily sus- pended. Sometimes used pathologically as the exact opposite of this, viz., as almost synonymous with asphyxia. Apo'da (Gr. a, not ; pous, podos, a foot). — A group of the Cirripedia, the sole representative of which has neither thoracic nor abdominal limbs. A'podemes (Gr. apodemeo, to go away, travel). — Processes which in the tenth, eleventh, twelfth, and thirteenth somites of the cephalothorax of the crayfish, project inwards and unite with one another in the thorax. Apo'lar (Gr. a, not ; polos, a pole). — A term applied to those nerve corpuscles which have no radiating processes. Aponeuro'sis (Gr. apo, from ; neuron, a sinew). — White fibrous tissue spread out in a sheet, which envelopes and binds down the muscles of different regions. Apo'physis (Gr. apophuo, I grow from). — A process or pro- tuberance of bone. Appendices epiploi'cae (L. appendix, an appendage; Gr. epiploon, the omentum). — Projections from the serous coat of the large intestine containing fat. Appendfcular (L. appendix, an appendage).— Applied to that part of the .skeleton (the limbs) which is attached to the axial skeleton. Appen'dix vermifor'mis (L. worm-like appendage). — A narrow tapering process of the caecum. Appen'dix v£sfcae (L. appendage of the bladder). — An ab- normal protrusion of a part of the mucous coat of the bladder through the muscular coat. Aproc'ta (Gr. a, not; proktos, the anus or seat). — A group of the Turbellaria in which there is no anal aperture. Apte'ria (Gr. a, not; pteron, a feather). — The spaces between the contour feathers in a bird. Aptery'gidae (Gr. a, not ; pteron, a wing). — A subdivision of the Ratitae in birds, which comprises the extinct wingless bird of New Zealand. 10 GLOSSARY. Ap'tychi (Gr. apto, I fasten). — Plates of shelly substance found sometimes in the terminal chamber of Ammonite shells. Aquaeduc'tus coch'leae (L. aqueduct of the cochlea).— A small canal leading from the cochlea of the human ear to the jugular fossa of the petrous bone. Aquseduc'tus Fallo'pii (L. aqueduct of Fallopius). — The canal in the temporal bone which transmits the facial nerve. Aquaeduc'tus Syl'vii (L. aqueduct of Sylvius). — A narrow canal connecting the third ventricle of the brain with its fourth ventricle, so named from its discoverer. Aquaeduc'tus vestfbuli (L. aqueduct of the vestibule). — A small canal leading from the vestibule of the human ear to the posterior surface of the petrous bone. Aqueous (L. aqua, water). — Watery. Applied to the humour filling the anterior chamber of the eye. Aquiferous canals (L. aqua, water; fero, I carry). — Water- bearing. Small canals which in some molluscs traverse the substance of the foot and open externally. Arach'nida (Gr. arachne, a spider). — A division of the Ar- thropoda which includes the spiders, scorpions, and mites. Arachni'dial mammilla (Gr. arachnc, a spider ; L. mantilla, a little teat). — The teat-like terminations of the ducts of the glands which secrete the web in the spiders. Arachnidial papillae (Gr. arachne, a spider; L. papilla, a nipple). — The terminations of the arachnidial mammillce. Arachni'dium (Gr. arachnc, a spider). — The glandular organ in which the web of spiders is secreted. Arach'noid (Gr. arachne, a spider's web). — The serous sac which forms the middle of the three enveloping membranes of the brain and spinal cord. Aranei'na (L. aranea, a spider). — The spiders. Ar'bor vi'tae (L. tree of life). — The name applied to the tree- like disposition of the grey and white nerve tissues in the cerebellum, as seen in a vertical section. Archaeoptery'gidaB (Gr. archaios, ancient ; ptcryx, a wing). — A class of extinct Oolitic birds, of which at present only one representative (Archaeopteryx) is known. ArchaeostS'matous (Gr. archaios, ancient, primitive; stima, stitmatos, the mouth, entrance). — A term applied to a gastrula when the blastopore does not entirely close up, but remains as the aperture by which the endodcrm of the organism communicates with the exterior. GLOSSARY. 1 1 Archego'nium. (Gr. archos, chief; gune, a female). — The organ which contains the female reproductive elements in cryptogams. Archen'tron (Gr. archos, chief; enter on, the intestine). — The pri- mitive alimentary sac in the embryo of some of the Invertebrata. Archiblas'tula (Gr. archos, chief; blastano, to germinate). — A term applied by Haeckel to the vesicular morula formed by the process of yelk division in the ovum of the Physemaria. Arctis'ca. — A group of the Arachnida. Arctoi'dea (Gr. arktos, a bear). — A group of the Carnivora which includes the bears, weasles, &c. Arctopithe'cini (Gr. arktos, a bear; pitheks, an ape). — The mar- mosets, small thickly-furred quadrupedal apes. Area germina'tiva (L. germinal area). — The area of the ovum in which the embryo appears. Area opa'ca (L. opaque area). — The marginal opaque ring which surrounds the pellucid area of the ovum, and from which the foetal appendages are developed. Area pellu'cida (L. pellucid or clear area). — The central por- tion of the germinal area from which alone the embryo is developed. Area vasculo'sa (L. vascular area). — The area of the blasto- derm in which the fcetal blood-vessels are developed. Are'olar (L. dreola, a little space). — Applied to a form of connective tissue which exhibits small spaces between its fibrous felt- work. Arreno tokous (Gr. arren, arrenos, a male ; tokos, a bringing forth). — A term applied to those small females amongst insects which lay eggs, from which only male offspring are developed. Ar'tery (Gr. aer, air ; tereo} I keep ; or it has been suggested probably Gr. arteria from arter, that by which anything is suspended). — A vessel which conveys blood from the heart, and the largest of which (the aorta) helps to suspend the heart. Arteries were thought by the ancients to contain air. Arthro'dia (Gr. art/iron, a joint). — A joint with nearly flat sur- faces, as in the articulations of the carpus, tarsus, and vertebrae, admitting motion on all sides. Arthrogas'tra (Gr. art/iron, a joint ; gaster, the stomach). — The scorpions and pseudo-scorpions, a division of the Arach- nida. 12 GLOSSARY. ArthrS'logy (Gr. arthron, a joint ; logos, a discourse). —The branch of Anatomy which treats of the joints. Arthro'poda (Gr. art/iron, a joint; pous, podos, a foot). — A division of the Invertebrata which comprises all those animals which have jointed appendages. Arthrozo'ic (Gr. arthron, a joint ; zoon, an animal). — A series of the Invertebrata which embraces the Arthropoda, Nematoscolices, and Chaetognatha. Articnla're (L. relating to a joint). — A bone of the lower jaw, which, in most of the Vertebrata but mammals, results from one of the ossifications of Meckel's cartilage. Articula'ta (L. articulus, a joint). — A group of Brachiopods in which the two valves of the shell are united by a hinge. Arti'culi (L. joints). — The joints of the cirri of the Crinoidea. Artiodac'tyla (Gr. artios, even; daktulos, a finger or toe). — A group of the Ungulata, the members of which have an even number of digits. Aryepiglot'tic ligaments. — Folds of mucous membrane extend- ing from the arytenoid cartilages to the epiglottis. Aryte'noid (Gr. arytaina, a pitcher or ladle ; eidos, shape). — The name of the two pyramidal cartilages of the larynx which are situated on the posterior border of the cricoid cartilage. Arytenoi'deus. — The muscle which passes from one arytenoid cartilage to the other. Ascala'bota (Gr. askalabos, a newt). — A group of the Lacertilia. As'ci (Gr. askos, a leathern bottle). — The name given to the sporangia of fungi, in which spores are produced by division of the protoplasm. Ascidia'rium (Gr. askos, a bag or leathern bottle ; cidos, form). — The structure which is formed by the ascidiozooids in the development of an Ascidian. Ascidioi'da (Gr. askos, a bag ; eidos, form). — A group of Mol- lusca, so called because they resemble in shape a two- . necked bottle. Asci'tes (Gr. askos, a bottle). — Dropsy of the abdomen ; so called from the bottle-like appearance to which it gives rise. Asco'nes (Gr. askon, a skin). — A family of the Calcisponga. As'cospores (Gr. askos, a leathern bottle ; spora, a seed). — Spores produced by division of protoplasmic masses, as in Torula, Afucor, &c. Asex'uaL — Not sexual ; applied to modes of reproduction in which sex takes no share, as gemmation, fission, &c. GLOSSARY. 13 Asphyxia (Gr. a, not; sphuxis, the pulse). — The state pro- duced by deprivation of air or deficiency of oxygen in the air breathed. Assimilate (L. ad, to; similis, like). — To convert food into nutriment ; to make like. Asterf dea (Gr. aster, a star). — A group of the Echinodermata which comprises the star-fishes. Asteris'cus (Gr. asteriskos, a little star). — The posterior and smaller otolith in the ear of Teleostean fishes. Astig'matism (Gr. a, not; stigma, a mark). — A term for dimness of vision supposed to arise from malformation of the crystalline lens. Astra'galus (Gr. astragalos, a die shaped like the ankle-bone). — One of the bones of the tarsus, which in man forms the ankle-bone. Atlas (Gr. the name of the god who was supposed to hold up the earth). — The first cervical vertebra which supports the skull- Atoll (L. attollo, I raise up). — A coral island consisting of a ring of coral having a lagoon in the centre. A'trial canals (L. atrium, a hall). — A pair of canals in the Tunicata, which open near the rectum. Atri'cha (Gr. a, not ; thrix, trfchos, the hair). — A subdivision of the Nematorhyncha which have no cilia. A'trium (L. the open court of a Roman house).— -The auricular portion of the heart. Also the cloaca of the Ascidioida. A'trophy (Gr. a, not; trepho, I nourish). — The wasting away of tissue for want of nourishment. Attol'lens (L. attollo, to raise up). — Raising up; elevating; applied to certain muscles which lift the parts to which they are attached. At'trahens (L. attraho, to draw up). — Drawing up. Applied to certain muscles which act in this way. Au'ricle (L. auricula, the outer ear). — The external ear. The receiving chambers of the heart are named auricles, because of the fancied resemblance of the auricular appendages to little ears.' Auri'culse (L. dim. of auris, the ear). — Perforated processes which arch over the ambulacra in the Echinidea. Anrf culo-orbicula'ris. — A round muscle attached to the pinna of the ear in some Vertebrates. Auto'phagi (Gr. aiitos, self; phdgo, I eat). — A term applied to birds which are able to run about and obtain their own food as soon as hatched. 14 GLOSSARY. A'ves (L. birds).— One of the divisions of the Vertcbrata. Avicula'rium (L. avicula, a little bird). — An appendage of the Polyzoa which somewhat resembles a bird's head. Ax'ial. — A term applied to that part of the skeleton which forms the main axis of the body. Axilla (L. the arm-pit). — The angle made by the leaf of a plant with the stem. Used also in human anatomy in its literal signification, to denote the angle between the arm and the trunk. Axis (L. a pivot). — The second cervical vertebra, which suj>- plies the pivot on which the head turns. Also applied to the central portion of the body round which the other parts are arranged. A'zygos u'vulae (Gr a, not ; zugos, a yoke). — A'muscle of the uvula. The term azygos is used as an adjective, to denote a muscle, vein, or other part of the body which is without a fellow. Bacil'lary (L. lacillum, a little staff). — Applied to the layer of the retina which contains the rods and cones. Bacillus (L. bacillum, a little staff).— A variety of Bacterium. Bacte'rium (Gr. bakterion, a staff). — The rod-like jointed filament which is found in putrefying organic infusions. Baguette (Fr. baguette, a small stick, a ramrod). — The term applied to the curved rods contained in the capsules into which the nucleolus of some Infusoria divides during con- jugation. Balaenoi'dea (L. bal&na, a whale). — A division of the Cctacea, comprising the right whale and the fin-fishes. Balan'idae (Gr. balanos, an acorn). — The sessile Cirripedia. Baleen (Vr. ba/eine, , whalebone). — The whalebone plates which in the Balaenoidea take the place of teeth. Earb (L. barba, a beard). — The term applied to the lateral processes of the rachis of the contour feathers of a bird. Bar'bule (L. dim. of barba, a beard). — Pointed processes of the barbs of the contour feathers of a bird. Basalia (Gr. basis, a pedestal).— The basal cartilages of the fins of the Elasmcbrjnchii. Basic'erite (Gr. basis, a pedestal ; keraia, a horn). — The second joint of the antennae of Crustaceans. GLOSSARY. 15 Basihy'al (L. lasts, the base ; hyoides, hyoid bone). — An ossi- fication of each corner of the hyoidean arch occurring in some fishes ; represented in Human Anatomy by the body of the hyoid bone. Basioccip'ital (L. basis, a pedestal, base ; occiput, the back of the head). — A bone of the skull which in Human Anatomy is represented by the basilar process of the occipital bone. Basiophthal'mite (Gr. basis, a pedestal ; ophthalmos, the eye). — The proximal joint of the eye-stalks in the Crustacea. Basfpodite (Gr. basis, a pedestal ; potts, podos, a foot). — That joint of the limb of an arthropod animal which is arti- culated to the body. Basytter'ygoid (Gr. basis, a pedestal ; pterygion, a little wing). — One of the bones of the vertebrate skull ; represented in Human Anatomy by the pterygoid plates. Basi-sphe'noid (Gr. basis, a pedestal; spken,*. wedge). — One of the bones of the vertebrate skull ; represented in Human Anatomy by the posterior part of the body of the sphenoid bone. Basi-tem'poral (Gr. basis, a pedestal ; L. tempora, the temples). — One of the bones of the vertebrate skull. Ba'sis cra'nii. — The base or floor of the skull. Bast or Bass. —The innermost layer of the bark of an exogenous tree. Batra'chia (Gr. batrachos, a frog). — A division of the Amphibia, sometimes termed Anura, which includes the frogs. Be'lemnites (Gr. belemnos, a dart). — An extinct group of Cepha- lopoda, the fossil remains of which were formerly termed thunderbolts. Belodon'tidae (Gr. belos, an arrow ; odous, odontos, a tooth). — A group of the Crocodilia, now extinct. Bi'ceps bra'chii (L. biceps, having two heads ; brachium, the fore- arm).— The double-headed muscle which flexes the fore-arm. Bi'ceps fe'moris (L. biceps, having two heads ; femur, the thigh). — One of the muscles of the thigh. Bicus'pid (L. bis, twice; cuspis, a pointed extremity). — Having two points, as the bicuspid teeth. Applied also to the valve between the left auricle and ventricle. Bi'furcate (L. bis, twice ', furca, a fork). — To divide into two branches, so as to give rise to a kind of fork. Bila'teral sym'metry (L. bis, in two ways ; latera, sides ; Gr. symmetria, proportion). — The similarity of parts on the right and left sides of a body. 1 6 GLOSSARY. Bile (L. bilis).— The alkaline secretion of the liver. Biliful'vin (bile ; fulvus, dark or reddish yellow).— A yellow colouring matter of the bile. Biliru'bin (bile; rubor, redness). — A red colouring matter of the bile. Biliver'din (Fr. bile, the bile ; vert, green).— A green colouring matter found in bile. BiSlogy (Gr. bios, life ; logos, a discourse). — The science which treats of the nature and properties of all living, as distinct from not living, matter. Bipolar (L. bis, twice ; polus, a pole). — Having two poles; applied to those ganglionic nerve corpuscles which have two radiating processes. Bisex'ual (L. bis, in two ways ; sexus, sex). — Not having the sexes united in the same individual. Bi'valve (L. bis, twice; valvce, folding doors). — Having a shell with two valves. BFvium (L. a place with two roads). — The two posterior ambulacra of the Echinidea. Blaste'ma (Gr. blastema, a bud, shoot). — The indifferent tissue of the embryo. Blas'tide (Gr. blastos, a germ). — A small, clear space in the segments of the ovum, which is the precursor of the nucleus. Blas'toccele (Gr. blastos, a germ ; koilos, hollow). — The central cleavage cavity of the morula produced by the segmenta- tion of the holoblastic ovum. Blas'toderm (Gr. blastos, a germ; derma, skin).— The germinal membrane from which the embryo is developed. Blastoi'dea (Gr. blastos, a bud; eidos, form). — A group of extinct Crinoidea. Blastomere (Gr. blastos, a germ; mcrcs, a part, portion). — The segments produced by the division of the ovum. Blas'tosphere (Gr. blastos, a germ ; sphaira, a ball, sphere). — The hollow sphere formed by the arrangement of the blastomcres on the periphery of the ovum. Blas'tostyle (Gr. blastos, a bud ; stylos, a style, pen).— The special stalk upon which the gonophores in the Hydro- phora are frequently developed. BS'tany (Gr. botane, an herb). — The branch of Biology which treats of vegetable life. Bra'chial (L. brachium, the fore-arm).— Relating to the arm. GLOSSARY. 1 7 Brachialis anti'cus (L. brachialis, relating to the arm ; anticus, forward, in front). — A muscle arising from the humerus and inserted in the ulna. BracM'ferous disk (L. brachium, the arm ; fero, I bear, carry). — The floor of the sub-umbrellar cavity in the Rhizosto- midas, from which the " arms " are given off. Brachio poda (Gr. brachion, an arm ; pous, a foot). — A division of the Mollusca having long ciliated arms and bivalve shells. Bra'chium (L. the fore-arm). — The division of the anterior extremity which lies between the shoulder and the elbow. Bra'chyceph'ali (Gr. brachus, short ; kephale, the head). — Those members of the human race which have short skulls, that is, with a cephalic index of 80 or above. Brachyu'ra (Gr. brachus, short ; oura, the tail). — A subdivision of the Crustacea in which the abdomen is comparatively small. Bract (L. bractca, a thin plate). — The modified leaf commonly found at the base of a flower-stalk in plants. Bran'chiae (Gr. gills). — The respiratory organs of fishes and some amphibians, adapted for breathing the air dissolved in water. Branchial (Gr. branchia, a gill).— Relating to the gills. Applied to the heart of an invertebrate animal, it signifies a heart which receives its blood from the vessels of the gills, and not from the systemic vessels. Bran'chio-car'diac canals (Gr. branchia, a gill ; kardia, the heart). — In the Crustacea, canals which bring the blood from the gills to the heart. BrancMogastero'poda (Gr. branchia, a gill ; gaster, the stomach ; potts, podos, a foot). — The Gasteropoda which breathe by gills. Branchio'poda (Gr. branchia, a gill ; pom, podos, a foot). — A group of Crustaceans having gills supported by the feet. Branchios'tegal membrane (Gr. branchia^ a gill ; stego, I cover). — A membrane which forms an inner covering to the gills in Teleostean fishes. Branchios'tegite (Gr. branchia, a gill ; stego, I cover). — A cover- ing, or protection for the gills. Bron'chial (Gr. bronchos, the wind-pipe). — Relating to the air- passages and lungs. Bron'chus (Gr. bronchos, the wind-pipe). — The name given to each of the two primary branches of the trachea. 1 8 GLOSSARY. Bry'ozoa (Or. bruon, moss; zoon, an animal). — Another name for the Polyzoa, which group of Invertebrata includes the sea-mats, &c, Buc cal (L. bueca, the mouth). — Relating to the mouth, as the buccal glands. Buc'cinator (L. bucca, the mouth, or buccino, to sound a trum- pet).— A muscle which forms a large part of the wall of the mouth, and is chiefly employed in blowing. Bulb (L. bulbils, an onion). — An underground bud covered with scales. Bui bivestl bull (L.vestibular bulbs). — Two leech-shaped masses containing veins, situate in the vestibule of the human female reproductive organs. Bol'bus arteriosus (L. arterial bulb).— The portion of the heart which in some animals, and in all vertebrate em- bryos, intervenes between the ventricle and the arteries, and which is usually rhythmically contractile. Bul'la (L. bulla, a bubble). — The convex osseous wall which bounds the tympanum in some Vertebrata. Burr. — A circular ridge which appears on the horn of deer, &c. Bur sa (Gr. a leather bottle). — A pouch ; a membranous sac containing fluid, interposed between parts which arc sub- ject to movement on one another to reduce friction. Bur'sa Entia'na. — The duodenal segment of the intestine in Elasmobranch fishes. Bursalis (L. bursa, a pouch). — A muscle, which in lizards is attached to the inner posterior wall of the orbit, and in birds to the sclerotic coat of the eye. Byssus (Gr. bassos, flax). — A cluster of silky threads by which the sea-muscle and other Lamellibranchiata attach them- selves to rocks. Cadaveric (L. cadaver, a corpse). — Corpse-like. Cadaveric rigidity is the stiffening of the muscles, or rigsr nwrtis which takes place after death. Cao cum (L. eaeus, blind). — The blind intestine, a diverticulum from the intestine proper in the Vertebrata. Calamus (Gr. kahunas, a reed). — The quill of a bird's feather. Calamus scriptorius (L. a writing-pen). — The angle formed by the divergence of the posterior pyramids of the medulla oblongata. GLOSSARY. 19 Calca'neum (L. calx, the heel). — The bone of the tarsus, which in man forms the heel. Cal'car (L. a spur). — The prominence on the anterior edge of the pes of a frog. The " spur " of some birds. Also a spur-like process in the Rotifera. Cal'car a'vis (L. a bird's spur). — The curved eminence in the lateral ventricles of the brain, usually called the hippocam- pus minor. Calca'reous (L. calx, lime).— Composed of lime or salts of lime. Cal'carine sul'cus (L. calcar, a spur; sulcus, a furrow). — The furrow of the cerebral hemispheres, which, by its projection into the lateral ventricles, gives rise to the hippocampus minor. Cal'ciform (L. calx, a pebble).— -Pebble-shaped. Calcispon'giae (L. calx, lime ; spongia, a sponge). — The sponges with calcareous skeletons, a division of the Porifera. Callo'sal gy'rus (L. callosus, having a hard skin ; gyrus, a circle made by running). — One of the cerebral convolutions. Callo'sity (L. callosus, having a hard skin). — A hardening of the integument. Callo'so-mar'ginal suTcus.— The sulcus or furrow which sepa- rates the marginal from the callosal cerebral convolution. Calorifa'cient (L. calor, heat; facio, I make). — Heat-producing. Calyx (Gr. kalyx, a cup, chalice).— The outer whorl of floral leaves in a flowering plant The expanded termination of the ureters in the kidney, which receive the urinary secretion from the urinary tubules. Also the " cup " of a Crinoid, or of Vorticella. (Plural, calyces.) Cam'bium. — A tissue composed of mucilaginous cells placed between the bark and young wood, or round the vessels of exogenous plants. Camelidae (Gr. kamelos, a camel). — The subdivision of the ruminants which embraces the camels. Canali cuH (L. little canals). — The canals in bone which contain the blood-vessels. A term for any small channel. Cana'lis anricula'ris (L. the auricular canal). — The constriction between the auricular and ventricular parts of the foetal heart. Cana'lis centra'lis (L. central canal).— The central canal which runs through the spinal cord. Cana'lis centra'lis modio li (L. central canal of the modiolus). — The largest of the canals in the modiolus of the ear. 20 GLOSSARY. Canalis membrana'cea (I,, membranous canal).— The central canal of the cochlea of the ear. Canalis reu'niens (L. the re-uniting canal). — The canal by which the sacculus of the internal ear communicates with the membranous canal of the cochlea. Cana lis spira'lis modio'li (L. spiral canal of the modiolus). — A small canal winding round the modiolus of the ear. Can'cellous (L. cancelli, trellis-work).— A term applied to the spongy form of bony tissue. Ca'nine (L. cams, a dog). — A term applied to the teeth next to the incisors, commonly called " eye " teeth, and which are well developed in the dog. Can'thus (Gr. kanthos, the corner of the eye). — The corner of the eye, formed by the junction of the eyelids. Cap'illary, or Capillary (L. capillus, a hair).— As an adjec- tive, fine, hair-like. As a substantive; one of the minute thin- walled vessels which unite the arteries and veins, and which are so called because of their hair-like size. Capillary lymphatics are those minute absorbents which form the network in which the lymphatics arise in the tissues. Capitulum (L. a little head). — Applied to the rounded body at the extremity of the manubrium in the antheridium of Chara, and similar plants. The head of flowers in the Composite. Also a cavity formed by the valves of the shell in the Cirripedia, in which the hinder part of the body is contained. A rounded process of bone. Cap'sulae atrabilia'riae (Fr. atrabiliarcy from L. ater, black ; bills, bile). — A term applied by the old anatomists to the supra-renal capsules. Ca'put cse'cum coli (L. the blind head of the colon).— Another name for the ccecum. Ca'put cor'nn posterio'ris (L. head of the posterior horn). — The enlargement at the back part of the posterior horn of the grey commissure of the spinal cord. Ca'put gallina'ginis (L. woodcock's head).— The crest of the urethra. Ca'rapace (a shield or covering).— In the Crustacea, that part of the exoskeleton which covers the cephalo-thorax. In the Chelonia, the dorsal exoskeleton or "shell." Carbonic acid gas, ~\ A poisonous gaseous compound of Carbonic anhy'dride, > oxygen and carbon, which is largely Carbonic dioxide, ) given off by all animals and plants. GLOSSARY. 21 Car'diac (Gr. kardia, the heart). — Relating to the heart. In the case of the stomach, the cardiac end is the end nearest the heart Car'dinal pro'cess (L. cardo, cardinis, a hinge). — A median process of the hinge line of the dorsal valve of the shell of the Brachiopoda. Car'dinal veins (Gr. kardia, the heart). — Veins which run backwards and forwards, parallel with the vertebral column, and return the blood to the heart in the vertebrate embryo, and which in fishes persist through life. Car'diograph. (Gr. kardia, the heart; grapho, I write).— An instrument for registering the movements of the pulse, and causing them to trace curves upon a moving sheet of paper. Car'do (L. a hinge). — The basal articulation of the maxilla of a cockroach. Cari'na (L. a keel). — The two united petals of such a flower as that of a bean or pea (papilionaceous). The keel-like process of the sternum of most birds. The piece of the valve of a Cirripede Crustacean which is intermediate between the calcified pieces (terga and scuta) of each valve. Cari'natae (L. carlna, a keel). — A group of birds provided with a keel to the sternum. Carnas'sial (L. cdro, carnis, flesh). — A term applied to the fourth premolar tooth of the dog, which bites scissor-like against the corresponding tooth in the other jaw. Carni'vora (L. cdro, carnis, flesh ; voro, I devour). — An order of the Mammalia, the members of which feed largely on flesh. Caro'tid (Gr. kara, the head; ous, the ear) — The principal arteries which convey blood to the head and lie close to the ears. Carpa'lia (Gr. karpos, wrist). — The bones of the carpus. Car'pel (Gr. karpos, fruit). — The modified leaf forming the pistil of a flower. Carpo'cerite (Gr. karpos, wrist ; keraia, a horn). — One of the segments of the antennae of some Crustaceans. Carpo'podite (Gr. karpos, wrist; pous,podos, a foot).— The fifth segment of the typical appendage of a Crustacean. Car'pus (Gr. karpos, wrist). — The wrist. The segment of the fore-limb which unites the manus to the fore-arm in the Vertebrata, and which in man forms the wrist. 22 GLOSSARY. Car'tilage (L. cartllago, gristle).— One of the animal tissues, commonly called " gristle." Cartila'gines ala'rom na'si (L. cartilages of the wings of the nostrils). — The lower lateral cartilages of the nose. Cartila'gines latera'les na'si (L. side cartilages of the nose).— The upper lateral cartilages of the nose. Cartila'gines mino'res vel sesamoi'dese (L. minor, or sesamoid cartilages). — The cartilaginous nodules in the membrane which attaches the lower lateral cartilages to the upper maxilla. Cartila'go triti'ce'a (L. wheat-shaped cartilage).— A cartilagi- nous nodule frequently found in the lateral thyro-hyoid ligaments. Camn'cula lachrymalis (L. caruncula, a little piece of flesh ; lacrimci) a tear). — The small reddish eminence in the inner corner of each eye. Carun'culae myrtifor'mes (L. caruncula, a little piece of flesh ; myrtus, the myrtle ; forma, form). — The little elevations of the wall of the vagina which remain after the rupture of the hymen. Casna'ridae.— The Cassowaries, a group of birds. Catallac'ta (Gr. katalatto, to change). — A group of the Protozoa, according to Haeckel. Cataly'tic (Gr. kataluo, to dissolve). — Having the power to in- duce chemical decomposition of a compound by its mere presence. Catame'nia (Gr. kata, according to ; ;/; (Gr. cheir, cheiros, the hand; mus, a mouse). — A family of Lemurs. Cheirop'tera (Gr. cheir, cheiros, the hand ; pteron, a wing). — A group of the Mammalia which comprises the bats. Chelse (Gr. chcle, a claw;. — The fourth pair of thoracic ap- pendages in the Crustacea, commonly known in the lobster as the great claws. Cheli'cera (Gr. chcle, a claw). — A pincer-likc appendage on each side of the mouth in the Scorpions. Chelo'nia (Gr. chelone, a tortoise). — A group of the Rcptilia which includes the tortoises and turtles. Chenomor'phaB (Gr. chcn, chcnos, a goose; morphc, form). — The goose-like birds. GLOSSARY. 25 Chev'ron bones (Fr. a rafter). — Downward processes of the caudal vertebrae of some of the Vertebrata which enclose the backward continuation of the aorta, Chias'ma (Gr. chiazo, I mark with the letter X, chi). — A crossing, as the chiasma of the optic nerves. Chilog'natha (Gr. cheilos, the upper lip ; gnatJws, the upper jaw). — A division of the Myriapoda which comprises the Milli- pedes, in which the mandibles are covered by a kind of lip. Chilo'poda (Gr. cheilos, the upper lip ; pous, podos, a foot). — A division of the Myriapoda which comprises the Centipedes. Chi/tin (Gr. chiton, a coat of mail). — The horny substance found in the exoskeletons of many of the Invertebrata. Chla'mydate (L. chldmydatus, clothed in the chlamys, a large woollen upper garment). — A term applied to those Branchiogasteropods which are provided with a mantle. Chlo'rophyll (Gr. chldros, green ; phyllon, a leaf). — The (usually green) colouring matter of plants, developed only under the influence of light. Chloro'sis (Gr. chldros, green). — The green-sickness. A disease due to retention of the menses. Cho'anae na'rium (Gr. and L. the funnels of the nose).— The openings of the posterior nares. Choles'terin (Gr. chole, bile; stear, suet). — A fatty substance found in bile and in some of the tissues. Chon'dro-cra'nium (Gr. chondros, gristle ; kranion, skull). — The cartilaginous model of the future skull in the vertebrate embryo. Chondros'teidae (Gr. chondros, gristle). — A sub-order of Ganoid fishes. Chor'da dorsalis (L. the dorsal or back cord). — The embryonic structure, which forms the axis round which the bodies of the vertebras are developed, and which in some of the Vertebrata persists through life. Chor'da tym'pani (L. cord of the drum). — A small branch of the facial nerve, which traverses the drum of the ear and supplies the submaxillary gland. Chor'dae tendi'nese (L. tendinous cords). — The cords which are attached on the one hand to the papillary muscles of the ventricles, and on the other to the flaps of the auriculo- ventricular valves of the heart. Cho'rion (Gr. cJiorion, skin). — The outer membrane which in the Mammalia surrounds the fcetus. 26 GLOSSARY. Cho'roid (Gr. choros, a choir; eidos, form). — A structure made up of a combination of small blood-vessels, as the choroid plexuses of the brain and the middle coat of the eye. Chroma'tophores (Gr. chroma, colour; phoreo, I bear, carry). — Pigment-sacs in the integument of the Cephalopoda. Chry'salis (Gr. chrusos, gold). — The pupa stage of an insect, so called because it is then sometimes of a golden colour. Chyle (Gr. chylos, juice). — The nutritious fatty material taken up by the lacteals. Chylifica'tion. — The conversion .of food into chyle. Chyme (Gr. chitma, a thing poured). — The material of the food which passes from the stomach to the intestine. Chymifica'tion. — The conversion of food into chyme. Cicatri'cula (L. a little scar).— The scar left after the falling of a leaf from a plant; the hilum or base of the seed of a plant. A term sometimes applied to the blastoderm or germinal membrane of an ovum. Cica'trix (Latin).— A scar. Cilia (L. ct!iuin, an eyelash). — Minute spontaneously vibratile filaments found in various parts of the body of both higher and lower animals. Ciliary ITgament (L. cftum, an eyelash ; ligo, 1 bind).— See Ciliary muscle, for which it is an obsolete term. Ciliary mus'cle (L. cllium, an eyelash). — A small muscle, situated between the anterior parts of the choroid and sclerotic coats of the eye. Ciliary pro'cesses (L. ctttum, an eyelash). — The anterior termination's of the choroid coat of the eye. Cilia'ta (L. cMum, an eyelashX — A division of the Infusoria. Cin'gulum (L. a girdle). — The basal part of the crown of a tooth. In the earthworm, a swollen region of the body into which more or fewer segments between the twenty- fourth and thirty-sixth enter. Cir'culus artlculi vasculo'sus (L. vascular circle of the joint). — The narrow vascular border formed by the synoviul vessels round the articular cartilages. Cir'culus cepha'licus (L. head-circle).— A circle formed l>y the arteries beneath the base of the skull in Teleostean fishes. Cir'culus major (L. greater circle). — A vascular ring in the ciliary muscle. Circ'ulus mi'nor (L. lesser circle). — A small vascular circle round the pupil. GLOSSARY. 27 Cir'culus veno'sus (L. venous circle). — A venous circle surrounding the base of the nipple of the mammary gland Circumduc[tion (L. circum, around; duco, I lead). — The rotation of a limb round an imaginary axis, so as to trace out a conical surface. Circumcesophage'al (L. drcum, around; Gr. oiso, future of phero, I bear; phagein, to eat). — Around the gullet, as the circumresophageal nerve-commissures found in the Crustacea. Circumval'late (L. circunt, around; vallum, a rampart). — Surrounded by a rampart, as the circumvallate papillae of the tongue. Cir'ri (L. cirrus, a lock of hair).— Root-like filaments given off from the articulations of some Invertebrata. Cirripe'dia (L. cirrus, a lock of hair; pes, pedis, a foot). —A division of the Crustacea having curled jointed feet. Clas'pers. — A pair of organs by the sides of the tail-fin of the male Rays, by which the female is grasped in the act of copulation. Claus'trum (L. that which shuts off). — A grey lamina on the outside of the corpora striata of the human brain. Cltvfcula ] (L' cl™cula> a little key).— The collar-bone. Cleidoxnastoi'deus (Gr. kleis, the clavicle ; and mastoid process). — One of the extrinsic muscles of the fore-limb. Clitel'lum (L. clitdlcE, a pack-saddle). — A region of the body of an earthworm which is swollen as compared with the other parts. See also Cingulum. Cli'toris (Gr. probably from kleio, I enclose). — A small elongated part of the female sexual organs in the higher mammals. Clo'aca (L. a sewer). — The common chamber which in many animals receives the urinary, generative, and intestinal secretions. Cly'peus (L. clipeus, or clypeus, a shield).— The broad flattened region of the head in a cockroach. Cne'mial crest (Gr. kneme, leg, shin-bone). — A protuberance of the proximal end of the tibia, which is well marked in all walking and swimming birds. Cni'dae (Gr. knide, a nettle). — The stinging thread-cells of the Coslenterata. Coagnla'tion (L. coagulum, a clot). — The process of clotting, which some fluids such as blood and lymph undergo. 28 GLOSSARY. Coccyge'al. — Relating to the coccyx ; composing the coccyx. Coccygomor'phae (Gr. kokkux, a cuckoo; morphe, form).— A division of the Carinate birds which includes the Cuckoos, Kingfishers, and Trogons. Coc'cyx (Gr. kokkux, a cuckoo). — The term applied to the four posterior vertebrae of man, which unite to form a structure similar to the beak of a bird. Cochlea (L. a snail's shell). — A structure forming part of the internal ear. Cocoon' (Fr. cocon; Gr. kokkos, a kernel). — The covering of an insect in the pupa state. Coelentera'ta (Gr. koilos, hollow; enteron, an intestine).— A group of the Metazoa which includes the Hydrozoa and the Actinozoa. Cce'liac artery (Gr. koilia, a hollow, the belly). — A short wide branch of the aorta given off just below the diaphragm. Cce'liac canal (Gr. koilia, the belly). — The largest of three canals which run in the arm in the Crinoidea, Ccenen'chyma (Gr. koine, in common ; f/tuma, something poured). — The intermediate skeletal layer developed in some Actinozoa in the process of gemmation or fission, by the new polype, and which is continuous with that of the other polypes. Cce'nosarc (Gr. koine, in common ; sarx, flesh). The common stem which sometimes unites the buds of a hydrozoon. Coitus (L. a coming together). — The congress of the sexes, Coleo'ptera (Gr. koleos, a sheath ; pteron, a wing). — The beetles, so called because the anterior chitinous wings form cases for the posterior membranous pair. Coleorhi'za (Gr. kbleos, a sheath ; rhisa, a root). — A wreath which encloses the radicle of an endogenous embryo. Colla'teral suTcus. — The groove in the cerebral hemispheres which gives rise to the collateral eminence in the lateral ventricles. Collete'rial glands (Gr. kolletos, glued).— Two glands in the cockroach which probably give rise to the cases of the eggs. Colli'culus (L. a little hill). — A small elevation. Colli'culus bul'bae ure'thrffi (L. little eminence of the bulb of the urethra). — A layer of spongy tissue surrounding the bulb of the urethra. Colli'culus ner'vi op'tici(L. little eminenceof the optic nerve). — A small eminence on the retina where the optic nerve expands. GLOSSARY. 29 Colli'culus semina'lis (L. little seminal eminence). — The crest of the urethra. Colloids (Gr. kolla, glue ; eidos, shape). — Substances like glue or gum. Substances which dissolve imperfectly, and which are but little diffusible through membranes. Colon (Gr. kolon, a limb, the great gut). — The second part of the large intestine. Colos'tmm (L. colostra^ the first milk of a cow after calving). — The first milk secreted after the birth of a child. Colum'bae (L. columba, a dove). — The pigeons ; a group of birds. Columella (L. a little column).— The projection above the collar of the stalk in some moulds, as in miicor mucedo, which projects into the sporangium. Also the name of a bone in the skull of the Lacertilia, which extends from the parietal to the pterygoid bones on each side. Also a core of connective tissue in the central cavity of a Crinoid. Columella au'ris (L. little ear column). — A small bone, which in birds, most reptiles, and some amphibia represents the ossicula auditus of the middle ear of the higher Vertebrata. Columella cochleae (L. little column of the cochlea). — The cen- tral pillar or modiolus of the cochlea of the internal ear. Colum'nse Berti'ni (L. columns of Bertini). — Prolongations of the cortical substance of the kidney, which pass between the 'pyramids. Colum'nse carne'ae (L. fleshy columns).— The muscular emi- nences on the wall of the ventricles of the heart. Colum'nae rec'ti (L. straight columns, or columns of the rectum). — Mucous folds of the rectum. Colum'nse ruga'nun (L. columns of the rugae).— An elevated ridge extending across the rugae, or fold of the mucous membrane of the vagina. Co'ma (Gr. koma, a deep sleep). — A state of unconsciousness brought about by morbid causes, such as compression of the brain. Co'mes (L. a companion; pi. comites). — A term applied to those veins which accompany the arteries. Com'missure (L. con, together ; mitto, I send). — A joining. A connecting link between two parts, as the commissures which unite the nerve ganglia in the Invertebrata. Complex'us (L. an embrace, a surrounding). — The name given to one of the dorsal muscles of the trunk. Cona'rium (L. conus, the fruit of the fir). — The pineal gland. 30 GLOSSARY. Con'cha (I* a shell).— The largest concavity of the external ear. Conchi'fera (L. concha, a shell ; fcro, I bear). — A name some- times applied to the Lamellibranchiata. Con'dyle (Gr. kondulos, a knuckle).— Generally applied to the flattened articular surface of a bone. Confer'vae (L. confervcre, to unite). — Vegetable organisms which consist of strings of united cells. Conglo'bate (L. con, together; globus, a ball).— A term applied to such glands as the lymphatic glands. ConglS'merate (I* con, together ; glomero, I gather in a round heap).— Applied to such glands as the salivary glands, pancreas, &c., which are also termed "racemose." Coni vasculo'si (L. vascular cones). — The conical convoluted branches of the vasa efferentia of the testicle. ConTdiophore (Gr. konis, dust ; phoreo, I bear). — The filaments which bear the conidia of fungi. C5ni'dium (Gr. konis, dust).— The spores of such fungi as Pent- cillium. Conjugation (L. conjugdre, to unite). — A mode of vegetable reproduction in which cells of adjacent hyphae unite. Conjuncti'va (L. ccnjugare, to connect). —The mucous mem- brane which lines the eyelids, and is reflected over the anterior part of the eyeball Con'nate (L. con, together ; natus, born).— A term applied to parts of plants (as the bases of leaves) which at an early stage of development become united. C6'nusarterid'sus(L. arterial cone). — The conical prolongation of the right ventricle from which the pulmonary artery springs. Co'nus medulla'ris (L. medullary cone).— The tapering portion of the spinal cord below the lumbar enlargement Co-or'dination (L. coorior, I come forth at once). — The acting together with regard to due force and sequence of different muscles. CopS'poda (Gr. kopcus, a chisel ; pous, podos, a foot). — A group of the Crustacea. Co'raco-brachialis (coracoid bone ; 'L.brachialis, belonging to the the arm). — One of the muscles on the ventral surface of the fore-limb, passing from the coracoid bone to the hume- rus in some Vertebrata. Cd'racoid (Gr. Kbrax, a crow; eidos, shape). — One of the bones of the shoulder-girdle in most vertebrate animals, repre- sented in man by tlie coracoid process of the scapula. GLOSSARY. 31 CSracomor'phae (Gr. korax, a crow ; morpke, form).— The crows and sparrow-like birds. Coralll'gena (Gr: korallion, coral; gennao, I produce). — The group of the Actinozoa which comprises the organisms which produce coral. Coral'lum (L. coral).— The calcareous secretion of the Actino- zoa, usually termed " coral." CorTmla (L. a little basket). — The common receptacle in the genus Aglaophenia of the Hydrophora which encloses groups of gonangia. Coria'ceous (L. corium, leather). — Leathery. Belonging to, or like leather. Co'rium (L. skin). — The true-skin or dermis. Cor'nea (L. corneus, horny). — The transparent modification of the sclerotic coat of the eye, which encloses the anterior part of the eyeball. Cornlcula laryn'gis (L. the little horns of the larynx). — Two small cartilaginous nodules of the arytenoid cartilages of the larynx. Cor'nu (L. a horn; pi. cornua). — Applied to horn- like projections of various structures in the body, as the cornua of the hyoid bone, cornua of the cerebral ventricles, £c. Cor'nu Am'monis. — Another name for the hippocampus major of the cerebral hemispheres. Corolla (L. corolla, a little crown). — The inner floral envelope of a flowering plant. Coro'na glan'dis (L. crown of the gland).— The rounded border of the penis. Coro'na radia'ta (L. radiating crown).— A term applied to the radiating fibres in the cerebral hemispheres. Co'ronary (L. corona, a crown). — Applied to the blood-vessels which supply the substance of the heart. Also the name given to one of the bones of the mandible in -some Vertebrata. Co'ronoid (Gr. korone, a crow ; eidos, form). — Crow-shaped ; as the coronoid process of the lower jaw. Cor'pora albican'tia (L. whitish bodies). — Two small white eminences on the base of the brain. Cor'pora Aran'tii (L. bodies of Arantius).— Thickenings on the edges of the semilunar valves of the arteries. Cor'pora bige'mina (L. two twin bodies). — The optic lobes of the brain of birds and fishes. 32 GLOSSARY. Cor'pora caverno'sa clltori'dis (L. cavernous body of the clitoris). — The two cavernous bodies which unite to form the clitoris. Cor'pora caverno'sa pe'nis (L. cavernous bodies of the penis). — The two bodies which form the principal part of the penis. Cor'pora genlcula'ta (L. the bodies with bent knee). — Two small eminences in front of the corpora quadrigemina of the brain. Cor'pora quadrige'mina (L. the four twin bodies). — Four hemispherical elevations of the roof of the iter of the brain in the higher Vertebrata, which correspond to the corpora bigemina of birds and fishes. Cor'pora stria'ta (L. striped bodies). — Two masses of nerve tissue, one in the floor of each lateral ventricle of the brain. Cor'pora trapezoi'dea- (L. trapezoid bodies). — Elevations found in the medulla oblongata of some mammals. Cor'pus adipo'sum (L. fatty body).— A body connected with the kidney in some Vertebrata. Also applied to the substance which fills up the space between the walls of the abdomen and the contained organs in the Insecta. Cor'pus callo'sum (L. hard body). — The mass of nerve tissue, which in the Mammalia unites the cerebral hemispheres. Cor'pus cflia're (L. ciliary body). — The toothed mass of grey matter in the olivary bodies of the medulla oblongata, usually termed the corpus dentatum. Cor'pus fimbria'tum (L. fringed body). — A narrow white band in each of the cerebral hemispheres. Cor'pus Highmoria'num (L. body of Highmore). — The incom- plete vertical septum formed in the testicle by a process of the tunica albuginea. Cor'pus lu'teum (L. yellow body). — The reddish-yellow cellular mass which forms in the Graafian follicle of a mammalian ovary after the discharge of the ovum. Cor'pus mammilla're (L. the mammillary body). — Another name for each of the corpora albicantia, which see. Cor'pus spongio'sum (L. spongy body). — A mass of erectile tissue which surrounds the urethra in the male. Cor'pus u'teri (L. body of the womb). — The part of the womb between the fundus and the neck. Corpus'cle (L. a little body). — The solid cellular bodies found in blood, lymph, &c. GLOSSARY. 33 Corpus'cula (L,. little bodies). — Small bodies found in the embryo sac of coniferous trees, and which correspond to the archegonia of ferns. Corpus'cula tac'tus (L. little touch bodies). — Small oval bodies found in those parts of the skin which are most sensitive to touch. Cor'tex (L. bark). — The bark of trees. The outer part of an organ. Cor'tical (L. cortex, bark). — Relating to the bark. Applied to the outer portion of an organ or organism. Cos'tal (L. costa, a rib). — Relating to the ribs. Costal respiration is that part of the respiratory function which is performed by the movements of the ribs. Cotyle'don (Gr. kotuledon, a cup-shaped hollow).— The temporary seed-leaf of an embryo plant. Applied also to each of the bunches of foetal villi which occur in the placentae of some mammals. Cotylo'phora (Gr. kotulos, a cup ; phoreo, I bear). — A group of Ruminants, the placenta of which exhibits cotyledons. Cox'a (L. the hip). — The basal joint of the leg in insects. Coxo'cerite (L. coxa, the hip; Gr. keras, a horn). — The basal joint of the antennae in the Crustacea. Coxo'podite (L. coxa, the hip; Gr. pous, podos, a foot).— The proximal joint of the typical limb of a Crustacean. Cra'nium (Gr. kranion, the skull). — The skull, brain-case. Cras'peda (Gr. kraspedon, a border or edge). — The convoluted cords attached to the mesenteries in the Actinozoa. Crassamen'tum (L. crassus, thick). — The solid clot of a coagulated material. Cremas'ter (Gr. kremao, I suspend).— A muscle of the abdomen found only in the male, and which supports the testicle. Crib'riform (L. cribrum, a sieve ; forma, shape). — Sieve-like. Applied to that portion of the ethmoid bone through the perforations of which the fibres of the olfactory nerves pass to the nasal cavities. Cri'co-arytenoi'dei later ales (L. lateral crico-arytenoid).— A pair of muscles which by their contraction close the glottis. Cri'co-arytenoi'dei posti'ci (L. posterior crico-arytenoid).— A paii of muscles which by their contraction dilate the glottis. Cri'co-thyroi'dei (L. crico-thyroid).— A pair of muscles which by their contraction stretch the vocal cords. Cri'coid (Gr. krikos, a ring; eidos, form).— The ring-like cartilage of the larynx. 34 GLOSSARY Cris'ta acus'tica (L. acoustic crest).— A small projection in the ampullae of the membranous semicircular canals of the ear. Cris'ta galli (L. cock's comb).— A ridge in the ethmoid bone of the skull to which the falx cerebri is attached. Cris'ta il'ii (L. crest of the ilium). — One of the borders of the iliac bone. Cris'ta ure'thrse (L. crest of the urethra). — A small ridge in the lining membrane of the urethra. Cris'ta vesti'buli (L. crest of the vestibule).— A vertical ridge in the vestibule of the ear. Crocodi'lia — A group of the Reptilia which includes the crocodiles, alligators, &c. Crocodi'lidae (Gr. krokodeilos, a crocodile). — A subdivision of the Crocodilia which comprises the crocodiles proper. Crossoptery'gidae (Gr. krossos, a fringe; pterux, a wing, fin). — A sub-order of Ganoid fishes. Cro't&phite (Gr. krotdpJws, the temples). — A term sometimes applied to the temporal artery, vein, and muscle. Cru'cial (L. crux, criicis, a cross). — In the shape of a cross. Cru'ra cfi'rgbri (L. legs of the cerebrum).— Two bundles of nerve fibres containing grey matter, which form the floor of the tier of the brain. Cms (L. the leg). — That portion of the lower or posterior extremity of the Vertebrata which lies between the femur and the tarsus. Also applied to any leg-like process. Crus'ta petro'sa (L. stony crust). — A substance resembling bone which coats the fangs of teeth, and in some cases fills up depressions in the enamel. Crypt (Gr. krupto, I conceal). — A term sometimes applied to simple tubular glands. Cryptoga'mia (Gr. kruptos, hidden ; gamos, marriage). — Plants, the reproductive organs of which are not readily visible, and which are sometimes termed " flowerless." Cryptor'chismus (Gr. krupto, I conceal; orchis, a testicle).— Retention of the testes in the abdomen. Crystalline lens. — The lens-shaped transparent body which is contained in the eyeball, and which assists in focussing the rays of light upon the retina. Crystalloids (Gr. krusta/los, crystal ; cidos, form). — Substances which are generally capable of being crystallized, and the solutions of which pass readily through membranes. Ctenobranchia'ta (Gr. ktcis, ktinos, a comb ; bronchia, a gill). — A group of the Branchiogasteropoda. GLOSSARY. 35 Cte'noid (Gr. kteis, ktenos, a comb; eidos, form). — A term applied to the scales of fishes which have comb-like edges. Ctenoph'ora (Gr. kteis, ktenos, a Comb j /A£nv, I bear). — A group of the Actinozoa which possess swimming organs in the shape of comb-like bands of cilia. Ctenosto'mata (Gr. kteis, ktenos, a comb; sfoma, stomatos, a mouth, opening). — A group of the Polyzoa. Cuboi'des (Gr. kubos, a cube; eidos, form). — One of the bones of the tarsus. Culm (L. culmus, a stalk). — The stem or stalk of grasses. Cuma'cea (Gr. kuma, a wave). — A group of the Crustacea. Cu'mulus (L. a heap). — A thickened portion of the lining cellu- lar layer of a ripe Graafian follicle, in which the ovum is embedded, and which is usually termed the discus proligerus. Cu'neiform cartilage (L. cuneus, a wedge ; forma, form). — A very small cartilaginous body placed on each side of the larynx in the fold of mucous membrane which extends from the arytenoid cartilage to the epiglottis. Cu'neiforme (L. cuneus, a wedge ; forma, form). — One of the bones of the carpus, sometimes termed ulnare. Also applied, according to one system of nomenclature, to three of the bones of the tarsus. Cu'pola (Italian, a dome). — The summit of the cochlea of the internal ear. Cur'sores (L. curro, I run). — According to the old scheme of classification of the class Aves, an order which included those birds which are destitute of the power of flight Cus'pidate (L. cuspis, the point of a weapon). — Having pointed eminences or " cusps." A term sometimes applied to the canine teeth. Cuta'neous (L. cutis, the skin).— Relating to the skin. Cu'ticle f ^ dim. of fufis, the skin). — Another name for the Cut! cilia i epidermis. In plants, the thin layer which (_ covers the epidermis. Cu'tis ve'ra (L. true skin). — The under vascular and sensitive layer of the skin, also termed the dermis. Cyano'sis (Gr. kuanos, dark-blue). — A condition in which the skin is blue, as the result of the non-closure of the foramen ovale between the auricles of the heart, and the consequent imperfect aeration of the blood. Cyathozo'oid (Gr. kuathos, a cup, bowl ; zoon, an animal ; eidos, shape). — A structure formed in the course of development in some of the Ascidioida. 36 GLOSSARY. Cy'cloid (Gr. kuklos, a circle; ados, shape). — A term applied to those fish-scales which are circular in form. Cyclo'sis (Gr. kuklosis, a moving round). — The circulation of fluids in the cells of plants. Cyclosto'mata (Gr. kuklos, a circle; stoma, stomatos, an opening, mouth). — A group of the Branchiogasteropoda. Cynoi'dea (Gr. kiton, kunos, a dog). — A group of the Carnivora which comprises the dogs, wolves, jackals, and foxes. Cynomor'pha (Gr. kudn, kunos, a dog; morp/ie, form). — The dog-like group of apes. Cyprinoi'dei (L. cyprinus, a carp). — A group of Teleostean fishes. Cypselomor'phae (Gr. cypselus, the generic name of the swifts ; morphe, form). — A subdivision of Carinate birds which comprises the swifts. Cyst (Gr. kustis, a bladder).— A bladder-like sac. Cys'tic (Gr. kustis, a bladder).— Belonging to a bladder, as the cystic duct which leads to the gall-bladder; also having bladders or cysts, as a cystic tumour. Cys'tid (Gr. kustis, a bladder). — The saccular ciliated embryo of the fresh-water Polyzoa. Cysti'dea (Gr. kustis, a bladder). — A group of extinct Echinoderms. Cy'toblast (Gr. kutos, a hollow body; blastos, a bud, shoot). — Another term for the nucleus of a cell Cy'tode(Gr.>fo/to,ahollowbody).— Anucleated protoplasmic cell. CytS'genous (Gr. kutos, a hollow body; gcnnao, I produce). — Cell-producing ; applied to a form of connective tissue. DactylS'podite (Gr. daktulos, a finger ; pous, pottos, a foot).— The terminal joint of the ambulatory appendages in some Crustaceans. Dar'tos (Gr. dcras, a skin). — One of the tunics of the scrotum. Dasypo'didae (Gr. dasus, rough, hairy; pous, podos, a foot). — The subdivision of edentate mammals which comprises the armadillos. Deca'poda (Gr. deka, ten ; pous, podos, a foot). — The dibranchiate cephalopods which have ten arms. Deci'dua refleza (K d?c;dnus, falling; reflectcre, to bend back). — That portion of the internal growth (decidua) of the pregnant uterus discharged in parturition which is reflected over the ovum. GLOSSARY. 37 Deci'dua sero'tina (L. dcdduus, falling; serofinits, slowly ripening). — The part of the decidua which intervenes between the ovum and the uterus. Deci'dua ve'ra (L. deciduus, falling; -vents, true). — That portion of the decidua which lines the uterus, except where the ovum is attached to it. Dscidua'ta (L. dectduus, falling). — A division of the Monodel- phia in which the maternal part of the placenta is thrown off with the foetus. Deciduous (L. deaduus, falling).— A term applied to those trees which shed their leaves annually ; also to the first, or milk teeth of mammals. Decus'sate (L. decusso, I cross over). — To cross over the middle line, as the nerve fibres do at the decussation of th e anterior pyramids. Defaeca'tion (L. de, down ;/, the spleen). — A branch of the portal vein which, in some Vertebrata, brings the blood from the spleen and intestines. Li'gament (L. ligo, I bind).— A band uniting bones or other structures. LIgamen'ta arcua'ta (L. the bow-shaped ligaments). — Two liga- mentous arches on each side of the diaphragm. Ligamen'ta la'ta (L. broad ligaments). — Two ligaments which support the uterus. Ligamen'ta subfla'va (L. yellowish ligaments).— Ligaments which connect the laminae of the vertebrae. Ligamen'ta vaginalia (L. enshcathing ligaments). — Strong tendinous bands of fibres which form the sheaths of the flexor tendons of the digits of the manus. Ligamen'tum nu'chae (L. ligaments of the neck).— A large sheet of connective tissue extending from the dorsal vcrtebnc to the occipital bones. Ligamen'tum te'res (L. rounded ligament). — A rounded liga- ment extending from the femur to the cotyloid notch of the acetabulum. Lig'nine (L. lignum, wood). — The essential constituent of woody fibre, formed of hardened cellulose. Li'gula (L. a little tongue). — The terminal piece of the labium in the Insecta. LimTxms (L. limbus, a border, hem). — A term applied to such sutures as that between the parietal and occipital bones. Li'nea aTba(L. white line). — A white fibrous structure extending from the ensiform cartilage to the pubis. Lfnea as'pera (L. rough line). — A prominent ridge on the femur. GLOSSARY. 75 Li'nea splen'dens (L. shining line).— A fibrous band in the pia mater of the spinal cord. Li'neae semiluna'res (L. semilunar lines). — Two curved linear spaces on the surface of the abdomen. Li'nese transver'sae (L. transverse lines). — Three or more lines which intersect the fibres of the rectus muscle of the abdomen. Lin'gua (L. a tongue). — A median process developed from the floor of the mouth in the Insecta. Lin'gual (L. lingua, a tongue). — Relating to the tongue, as the lingual branch of the fifth nerve. Lin'gula sphenoidalis (L. wedge-shaped tongue). — A small bony ridge in the sphenoid bone. Li'quor amni'i (L. amniotic fluid). — The fluid contained in the amniotic cavity which surrounds the embryo. Li'quor sangui'nis (L. blood liquor). — The fluid part of the blood in which the corpuscles float ; the blood minus its corpuscles. Lfthocyst (Gr. lit/ios, a stone; kustis, a bladder).— A term applied to the sacs containing mineral particles frequently found in the Medusae, and supposed to be auditory organs. Locate. — Made up of lobes. Applied to the tails of fishes when the integument is continued to the bases of the fin-rays. Lobe (Gr. lobos, the lower part of the ear). — Applied to parts of organs similarly shaped to the lobe of the ear. LoT)i inferio'res (L. inferior lobes). — A pair of enlargements on the lower surface of the brain in some Vertebrata, LoTmle. — A small lobe; applied to the subdivisions of the lobes of an organ. LoTmlus cauda'tus (L. tail-like lobe).— One of the lobes of the liver. Lo'bulus qnadra'tus (L. square lobe). — One of the lobes of the liver. Lo'bulus Spige'lii (L. lobe of Spigelius). — One of the lobes of the liver. LS'chia (Gr. lochios, belonging to childbirth). — The uterine discharges which take place after parturition. Lo'cule (L. a little space).— A little hollow. LS'culi (L. little spaces). — The spaces between the septa in the Actinozoa. Lo'cus caeruleus (L. dark-blue place).— A collection of pigment in the fourth ventricle of the brain. 76 GLOSSARY. Lo'cus ni'ger (L. black place). — A layer of dark matter in each of the crura cerebri of the brain. Lo'cus perfora'tus anti'cus (L. anterior perforated space). — A depression near the entrance of the Sylvian fissure of the cerebrum. Lo'cus perfora'tus postfcus (L. posterior perforated space). — A deep depression between the peduncles of the cerebrum. Longis'simus dor's! (L. longest muscle of the back). — A large dorsal muscle of the trunk in the higher Vertebrata. Lon'gus col'li (L. long muscle of the neck). — A muscle of the neck situate in front of the vertebral column. Lfiphobran'chii (Gr. lophos, the neck; branchia, a gill).— A group of Teleostean fishes. Lo'phophore (Gr. lophos, neck; pJwreo, I bear). — The disc in the Polyzoa which bears the mouth. Lophos'teon (Gr. lophos, neck; osteon,'* bone). — The central keel-bearing ossification in the sternum of birds. Lorica'ta (!„ lorica, a cuirass, corselet). — A group of insecti- vorous Edentates in which the dorsal region of the body is covered by a carapace. Lucerna'rida (L. lucerna, a lamp). — A group of Hydrozoa. Luette ve'sicale (Fr. uvula of the bladder). — A slight elevation of the mucous membrane of the bladder. Lum1>ar (L. lumbus, the loin). — Relating to the region of the loins. Lum'bo-sa'cral plexus (L. lumbus, the loin ; sacrum). — A plexus formed in the frog by the seventh, eighth, and ninth spinal nerves. Lumbricales (L. worm-shaped muscles). — Four muscles of the digits of the manus and the pes. Luna re (L. moon-shaped bone). — One of the bones of the carpus, sometimes called intermedium, also semilunare. Lu'nula (L. little moon). — The white crescentic portion near the root of a nail ; applied also to the thin parts of the margins of the semilunar valves of the heart Lymph (L. lynipha, water). — The colourless fluid absorbed from the tissues by the lymphatics. Lymphatics (L. lympha, water). — The special absorbent vessels distributed over the system, exclusive of those of the small intestine which are usually termed lacteals. Ly'ra (L. a lyre). — A triangular striated portion of the corpus callosum of the brain. GLOSSARY. M. Macrauche'nidae (Gr. makrauchen, makrauchenos, long-necked). — An extinct family of the Perissodactyla. Ma'cromere (Gr. macros, long; meros, a part). — The larger of the two unequal masses into which the vitellus divides in the development of the Lamellibranchiata, termed by Rabl the " vegetative cell." Macru'ra (Gr. makros, long ; oura, tail). — A subdivision of the Podophthalmia (Crustacea), in the members of which the abdomen is largely developed. Ma'cula gennina'tiva (L. germinal spot).— The nucleoltrs of the germinal vesicle of the ovum. Ma'cula lu'tea (L. yellow spot).— The bright spot on the retina of the eye, which is most sensitive to the action of light. Madrepo'ric canals.— Tubular prolongations of the circular ambulacral vessel in the Echinodermata. Madrepo'ric tu'bercle.— A convex porous plate on the aboral face of some Echinoderms. Madrepo'riform. — A term applied to the madreporic tubercle. Madrepo'rite. — Another name for the madreporic tubercle. Malacosco'lices (Gr. mdlakos, soft ; skdlex, a worm). — A divi- sion of the Invertebrata proposed by Huxley to include the Polyzoa and the Brachiopoda : the name signifies the connexion of these groups, on the one hand with the Mollusca, on the other with the Worms. Malacostra'ca (Gr. malakos, soft). — A division of the Crustacea which includes the Podophthalmia, the Cumacea, the Edriophthalmia, and the Stomatopoda. Malacozo'ic series (Gr. malakos, soft ; zoon, an animal). — A series of the Invertebrata which includes the Malacoscolices and the Mollusca. Malar (L. mala, the prominence of the cheek). — The cheek- bone. Malle'olar (L. malleolus, a little hammer, the ankle). — A bone in the Ruminantia which articulates below with the cal- caneum, and above with the astragalus. Applied also to two small arteries distributed to this region. Malle'olus (L. a little hammer). — The name given to a process of the tibia and of the fibula. Malleus (L. hammer). — The small bone of the middle ear which articulates on the one hand with the tympanic 78 GLOSSARY. membrane, on the other with the incus. Also the name of each lateral piece of the armature of the pharynx in the Rotifera. MallS'phaga (Gr. mallos, lock of hair ; phago, I eat). — A family of insects parasitic upon mammals and birds, and which feed upon the feathers and hair. Malpl'ghian cap'sules (L. capsules of Malpighi). — The dilated extremities of the uriniferous tubules of the kidney. Malpi'ghian corpus'cles (L. corpuscles of Malpighi). — Rounded collections of nucleated corpuscles found in the spleen. Mammalia (L. mamma, the breast). — The class of Vertebrata which includes all those animals which suckle their young. Mam'mary glands (L. mamma, the breast).— The glands in the Mammalia which secrete milk for the nutrition of the young ; the breasts. Mam'millary (L. mamma, the breast). — A name applied to the tubercles or metapophyses of the vertebrae. Man'dible (L. mando, I chew).— In the Vertebrata, the lower jaw ; in the Arthropoda, the upper pair of jaws ; in the Cephalopoda, the beak ; in birds sometimes applied to both rostra of the beak. Mann'brium (L. a handle). — The handle-shaped sac which is suspended from the centre of the disc in the Medusae. Applied, in the Vertebrata, to the handle-like process of the malleus and of the sternum ; in Chara, the process which projects into the antheridium from each of its eight pieces. Ma'nus (L. the hand). — The terminal segment of the anterior extremity, which in man forms the hand. Mar'ginal bones. — The name given to certain added bones on the radial and ulnar edges of the manus in the Ichthyo- sauria. Mar'ginal gy'rus. — One of the convolutions of the brain. Mar'go acu'tus (L. acute margin). —The right or lower border of the heart Mar'go obtu'sus (L. obtuse margin).— The upper or left border of the heart. Marslpobran'chii (Gr. marslpos, a purse, bag ; bronchia, a gill). — An order of fishes which includes the Lampreys, Hags, &c., which have pouch-like gills. Marsupia'lia (L. marsvpiumt a pouch).— An order of Mam- malia provided with an abdominal pouch for the reception of the young, which are brought forth at a very early stage of development. GLOSSARY. 79 Marsu'pium (L. a pouch). — The abdominal pouch in the Marsupialia. Also another name for the pecten of the eye. Masse'ter (Gr. massaomai, I chew). — One of the muscles of mastication, passing from the zygomatic arch to the lower jaw. Mas'tax (Gr. mouth). — The muscular pharynx of the Rotifera. Mastica'tion (Gr. masaomai, I chew). — The process of chewing the food. Mas'ticatory (Gr. masaomai, I chew). — Engaged in mastica- tion ; applied to those organs which are engaged in chewing. Masti'gopods (Gr. mas fix, a whip j pous, podos, a foot). — A term applied to those Protozoa which possess cilia or flagella. Mas'toid (Gr. mastos, a breast ; eidos, shape). — Nipple-shaped. Applied to the process of the temporal bone behind the ear. Mastoi'do-hu'meral muscle. — A muscle which in some Verte- brata passes from the skull to the cervical region. Mate'ria alimenta'ria (L. alimentary material). — The materials of the food. Ma'trix (L. a womb). — The substance in which anything is embedded. Maxilla (L. a jaw). — In the Arthropoda, the lower pair or pairs of jaws ; in the Vertebrata applied to both upper and lower jaws, the principal bones of which are termed in- ferior and superior maxillary respectively. Maxiriiform (L. maxilla, jaw ; forma, shape). — Jaw-like ; jaw- shaped. Maxillipede (L. maxilla, a jaw ; pes, pedis, a foot). — Foot-jaws. The appendages of the Crustacea which serve both for masticatory and ambulatory purposes. Maxillo-mandi'bular nerve.— A division of the fifth cerebral nerve which supplies the maxilla and the mandible. Maxirio-tur'binal. — Another name for the inferior turbinated bone of the face. Mea'tus (L. a way, path, passage).— A small canal; as the external auditory meatus. Mea'tus audito'rius exter'nu,s (L. external auditory canal). — The passage which leads from the exterior to the tympanic membrane of the ear. Mea'tus urina'rius. — The external opening of the female urethra. 80 GLOSSARY. Mec'kel's car'tilage.— The cartilage of the chondrocranium which forms the axis of the mandible. Meco'nium (Gr. mckon, a poppy). — Poppy-juice; the faeces passed by a new-born infant Me'dian (L. medius, middle).— Middle. M6dias'tinum (L. mcdtus ; sto, I stand).— A middle partition ; as the mediastinum formed in the thorax by the union of the two pleurae. Me"difur'ca (L. mcdius, middle; furca, a fork). — The middle apodemes which project into the thorax of some Insecta. Me'dius (L. middle). — The third digit. Medulla (L. marrow). — The marrow of bones; the pith of a plant Medulla oblonga'ta (L. elongated marrow). — That portion of the cerebro-spinal axis which lies between the spinal cord and the iter of the brain. Medu'sae. — The sea-nettles or jelly-fishes, so called because their tentacles resemble the snakes which formed the hair of the Medusa, the chief of the Gorgons. Medu'soid (Gr. Medusa-like). — A term applied to the zooids in the Hydrozoa which produce reproductive organs. Meibo'mian (named from Meibomius, who first discovered them). — The name given to certain glands on the inner surface of the eyelids. Mela'nochroi (Gr. melds, melanos, black ; chroia, skin, com- plexion).—A group of the human race which includes the " dark-whites." Membra'na adamanti'nea (L. adamantine membrane).— A name applied to the epithelium on the surface of the pulp of a tooth. Membra'na cap'sulo-pupilla'ris (L. capsular membrane of the pupil). — A highly vascular membrane which in the foetus surrounds the crystalline lens of the eye. Membra'na e"boris (L. ivory membrane). — The external cellular layer of the pulp of a tooth. Membra'na granulo'sa (L. granular membrane). — The lining membrane of the Graafian vesicles of the ovary. Membra'na lim'itans (L. limiting membrane). — The membrane which bounds the anterior and posterior surfaces of the retina. Membra'na nic'titans (L. winking membrane). — The third eye- lid in birds, amphibia, and some mammals, formed by a fold of the conjunctiva. GLOSSARY. 8 1 Membra'na preforma'tiva (L. preformed membrane). — A deli- cate membrane said to cover the dental pulp before the calcification of the teeth. Membra'na pro'pria (L. special membrane). — The basement membrane of secreting organs. Membra'na pupilla'ris (L. pupillary membrane). — A delicate membrane by which in the foetus the pupil is closed. Membra'na saccifor'mis (L. sac-shaped membrane). — The syno- vial membrane of the fore-arm. Membra'na semiluna'ris (L. semilunar membrane). — A mem- brane attached to the septum in the syrinx of birds. Membra'na tym'pani (L. membrane of the drum). — The mem- brane which closes externally the tympanum or drum of the ear. Membra'na tympanifor'mis inter'na (L. internal drum-shaped membrane). — The inner wall of that part of the bronchus of birds which forms part of the syrinx. Membra'na velamento'sa (L. covering membrane).— A mem- brane in the internal ear. Mem'brane cos'to-cS'racoid. — A layer of fascia attached supe- riorly to the clavicle, and inferiorly to the coracoid process and first rib. Menin'geal (Gr. mentnx, a membrane). — Applied to certain arteries and veins of the neck. Menis'cus (Gr. meniskos, a half-moon). — A disc into which the fibro-cartilaginous rings which connect the presacral ver- tebras in birds are continued. Men'stmation (L. mensis, a month). — The periodical uterine discharges. Men'tal fora'men (L. mentum, the chin ; foramen, an opening). — An opening in the lower jaw through which the inferior dental nerve and artery pass. Men'to-hy'oid muscle (L. mentum, the chin; Gr. filicides, hyoid bone). — An occasional muscle passing from the body of the hyoid bone to the chin. Men'to-Mecke'lian element (L. mentum, the chin). — The portion of Meckel's cartilage which ossifies to form the chin. Men'tum (L. the chin).— The front median plate of the labium in the Insecta. Meroblas'tic (Gr. meres, a part ; llastos, a germ). — Applied to those ova of which only a part of the yolk undergoes segmentation. 8 2 GLOSSARY. MerS'cerite (Gr. mcros, the thigh ; kcras, a horn). — One of the joints in the antennae of the Crustacea which represents the tneropodite of the typical Crustacean appendage. Meroistic (Gr. meros, a part; don, an egg). — A term applied to the ovaries of insects when they secrete not only ova, but also vitelligenous cells. Mero'podite (Gr. mcros, the thigh, ham ; pous,podos, a foot). — The fourth joint of the typical appendage in the Crustacea. Merosto'mata (Gr. meros, a part; stdma,y amceboid cells. /Wu'doscope (Gr. pseudos, false; skopeo, I behold). — An in- strument by means of which hollow objects are made to appear convex, and convex bodies hollow. /fceudo'vary (Gr. pseudos, false ; L. ovum, an egg). — In some insects the organ within which the young are developed. /fcendo'vnm (Gr. pseudos, false; L. ovum, an egg). — A cell formed in the pseudovary of some insects, and which sub- sequently developes into the larva. /feittacomor'phae (Gr. psittakos, a parrot; morphe, form).— The parrots, a group of carinate birds. /Was ma'jor (Gr. psoa, the loins; L. major, greater).— A muscle passing from the posterior dorsal or lumbar vertebrae to the femur. /Was mi'nor (Gr. psoa, the loins ; L. minor, smaller). — A muscle passing from the under surface of the posterior dorsal or lumbar vertebra; to the ilium or pubis. GLOSSARY. Iiy /terocar'diac os'sicle (Gr. pteron, a wing ; kardia, a stomach ; L. ossiculum, a little bone). — A small triangular ossicle in the skeleton of the stomach in some Crustacea. ./teroclomor'phse (Gr. pterodes, the generic name of the sand- grouse ; morphe, form). — A group of carinate birds com- prising the sand-grouse. /terodac'tylus (Gr. pteron, a wing ; daktulos, a finger). — An extinct flying reptile belonging to the Pterosauria. -/tero'poda (Gr. pteron, a.vf\r\g;pous.podos1 a foot ).— A division of the Mollusca which swim by wring-like processes at- tached to the head. /terosau'ria (Gr. pteron, a wing ; sauros, a lizard). — A group of extinct flying reptiles. /tero'tic (Gr. pteron, a wing; ous, ofos, the ear). — An ossifica- tion of the skull occurring in some Vertebrata, between the pro-otic and the epiotic bones. /ter'ygoid (Gr. pterux, a wing; eidos, form). — The name of a pair of bones, in the facial apparatus of some Vertebrata, behind the palatines ; known in Human Anatomy as the pterygoid plates of the sphenoid bone. /terygoi'deus pro'prins (L. special pterygoid).— A small muscle sometimes occurring, and which passes from the great wing of the sphenoid bone to the palate bone or pterygoid plate. /terygomaxillary fissure.— A fissure which separates the external pterygoid plate from the superior maxillary bone. Pterygomaxillary ligament — A narrow band of tendinous fibres stretching from the internal pterygoid plates to the lower jaw. /terygopa'latine artery.— A small branch of the maxillary artery. /terygopa'latine canal. — A small canal between the internal pterygoid plate and the palate bone which lodges the pterygopalatine artery. Tterygosto'mial plates (Gr. pterux, a wing ; stoma, an opening). — The portions of the carapace in the Brachyura which run forwards parallel with the axis of the body. /'ter'ylae (Gr. pterux, a wing). — The bands of contour feathers in birds. Pto'sis (Gr. ptoo, I fall). — Inability to raise the upper eyelid. /'ty'alin (Gr.ptuo, I spit). — The nitrogenous essential principle of saliva. Il8 GLOSSARY. PuT)is (L.pitbes, the region of the groin). — A bone of the pelvis which in man forms the anterior portion of the vs innoini- natinn. Pu'bo-fe'moral. — The name given to a ligament entering into the formation of the capsule of the hip-joint. PuTbo-ure'thral. — An occasional muscle of the perina?um. Pu'bo-ve'sicaL — An occasional muscle of the perinoeum passing from the back of the symphysis pubis to the neck of the bladder. Puden'da(L./////er olfacto'rium (L. olfactory swellin ).— The middle root of the olfactory nerves. Tuber'cula quadrige mina (L. tubercu'um, a small swelling; quadrigeminus* four at a birth). — Another name for the corpora quadrigemina of the brain. Tuber' culum. — A small eminence or swelling, as the tubercitlum pharyngeum, which is the tubercle from which the median muscular band attaching the pharynx to the skull springs. Tubero'sity (L. tuber, a lump, swelling). —A thick prominence of bone, usually giving attachment to muscles. Tu'buli rec'ti (L. straight tubules). — The straight portion of the uriniferous tubules of the kidneys. Tu'buli semgnFferi (L. semen-bearing tubules). — The small con- voluted tubules in which the seminal fluid is secreted. Tu'buli urini'feri (L. urine-bearing tubules). — The small tubes of the kidney which collect the urine. Tubulidenta'ta (I* tubidus, dim. of tubus, a pipe, tube ; dens, dentis, a tooth). — A group of the insectivorous Edentata, the single genus of which has teeth which are traversed by a number of canals. Tu'nica abdomina'lis (L. abdominal tunic). — A strong mem- brane which in some Mammalia contributes to the support of the viscera. Tu'nica adventi'tia (L. foreign or outside tunic).— A name applied to the external coat of the arteries. Tu'nica albugl'nea (L. white tunic). — The outer capsule of the testicle. Tu'nica-cho'rio-capilla'ris (L. capillary choroid coat). — The inner layer of the choroid coat of the eye. Tu'nica choroi'dea (L. choroid tunic). — Choroid coat of the eye. Tu'nica granuld'sa (L. granular tunic). — The granular lining of the Graafian follicles of the ovary. Tu'nica pro'pria (L. special tunic). — The membranous lining of the semicircular canals. Tu'nica vagina'lis (L. ensheathing tunic). — A serous sac en- closing the testicle. Tu'nica vagina'lis 6'culi (L. ensheathing tunic of the eye). — A sheath of fascia surrounding the eyeball. Tu'nica vasculo'sa tes'tis (L. vascular tunic of the testicle). — A layer of delicate and highly vascular areolar tissue which surrounds the testicle. Tunica'ta (L. tunka, a tunic).— Another name for the Ascidi- oida — which see. GLOSSARY. 151 Tu'payae (tupaia, the name given by the natives of Sumatra, where and in India these animals are found). — A genus of the Insectivora which approach the Lemurs. Turbella'ria (L. turbo, I disturb). — A group of free-swimming organisms belonging to the division Trichoscolices, and so named because of the currents they cause in the water in which they live by means of their cilia. Tur binated (L. turbo, a turning round). — The name given to certain twisted bones entering into the formation of the nasal and olfactory chambers. Tnrnicimor'phse. — A group of birds. Tuta'mina 6'ciili (L. defences of the eye). — A name sometimes applied to the eyelids. TylS'poda (Gr. tulos, a swelling, pad ; pous,podos, a foot). — The Camels. Tym'pamun (L. a drum). — The middle ear. Also a chamber in the syrinx of birds. Typblo'pidae (Gr. tuphlos, unseen; pous, podos, a foot). — A group of the Ophidia. Typh'losole (Gr. tuphlos, unseen).— A thick fold of the wall of the intestine, which in the Lamellibranchiata and in the earth-worms projects into the interior of the intestinal cavity, and which is not seen from the exterior. Ty'rosin (Gr. turos, cheese). — A nitrogenous compound result- ing from the decomposition of proteid substances. U. Ul'na (Gr. olene, the elbow). — The bone of the antebrachium, the proximal end of which forms the elbow in man. Ul'nar. — Relating to the ulna, as the ulnar artery. TJlna're. — A bone of the carpus which articulates with the ulna. Ulotri'cM (Gr. oulos, woolly ; thrix, trichos, hair). — The division of the human race which embraces all those varieties which have crisp, woolly hair. Umbili'cal cord (L. umbilicus, the navel). — The navel string. The cord which connects the foetus with the placenta. TJmbili'cal ve'sicle (L. umbilicus, the navel).— The vesicle which contains that portion of the vitellus which serves as nutriment for the embryo. IS 2 GLOSSARY. Umbillcns (L. the navel). — The point in the middle line of the abdomen at which the somatopleures of the foetus unite. Also the name given to two apertures (superior and inferior) in the calamus of a bird's feather. Um'bo (pi. umbones, L. a boss). — The beak of a bivalve shell. Also a depression in the integument of the larva of an Echinoderm. Un'ciform (L. uncus, a hook ; formis, shape). — One of the bones of the carpus, also termed undnatum and hatnatiun. Un'cinate (L. uncus, a hook).— Hooked. Applied to a process of the ethmoid bone. Un'gual phalan'ges (L. unguis, a nail). —The terminal phalanges of the digits, so called because provided with nails or claws. Un'gues (L. unguis, a nail). — Applied to the pointed claws which terminate the legs in the Insecta. Un'guis (L. a nail). — The narrow stalk by which the alae of a papilionaceous flower are attached to the corolla. Un'gulata (L. ungula, a hoof). — A group of the Non-deciduate Mammalia. Unguligrade (L. ungttla, a hoof; gradus, a step). — Applied to those animals which walk upon hoofs, which consist of the ungual phalanges encased in thick horny sheaths. Unipolar (L. unus, one ; polus, the pole). — Having a single pole. Applied to those ganglionic nerve cells which have but one radiating process. TJ'nivalve (L. unus, one ; valva, folding doors). — Applied to those Mollusca which have shells composed of a single piece. U'rachus (Gr. ouron, urine ; echo, I hold). — One of the liga- ments of the bladder formed by the remaining constricted portion of the allantois of the foetus. Ure'a (Gr. ouron, urine). — A nitrogenous substance found abundantly in the urine, and produced by the waste 01 nitrogenous material both in the food and in the tissues. Ure'ter (Gr. oureter, the urinary duct). — A duct leading from the kidney to the urinary bladder. Ure'thra (Gr. oiircthrd). — The canal leading from the urinary bladder to the exterior. Uri'na ciT>i (L. urine of food).— The name given to the urine passed immediately after food has been taken. Uri'na po'tus (L. urine of drink). — The name given to the urine passed immediately after a quantity of fluid has been drunk. GLOSSARY. 153 Url'na san'guinis (L. urine of the blood). — A term applied to the urine evacuated at times when neither food nor drink has been recently taken, as, for instance, that evacuated upon rising in the morning. Urini'ferous tubes (L. urine-bearing tubes). — The tubules in which the urine is secreted, and by which it is poured into the calyces of the ureters. Uro-car'diac process (Gr. oura, the stern ; kardia, the stomach). — A process of the cardiac piece of the stomach in some Crustacea. TTro-car'diac tooth (Gr. oura, the stern ; kardia, the stomach). — A process of the pre-pyloric ossicle in the stomach of some Crustacea. TTro- chord (Gr. oura, the stern, tail; cJwrde, a string). — The central axis in the Ascidioida. Uro'dela (Gr. oura, the tail ; delos, distinct). — A group of the Amphibia having a distinct and often long tail. TTrogas'tric (Gr. oura, the stern, tail ; gaster, the stomach). — The name given to two lobes of the carapace in the Brachyura. TJrohy'al (Gr. oura, the stern; hyoid bone). — The posterior ossification of the hyoidean arch in fishes. Uropoie'tic (Gr. ouron, urine ; poietikos, making). — A system of organs in the Invertebrata which are concerned in eliminating the nitrogenous waste from the blood. Uropy'gial (Gr. oura, the tail ; pugaios, the buttocks). — The name given to a gland which in many birds secretes an oily fluid spread by the bird over its feathers, the gland being situated in the integument which covers the coccyx. TJrosa'cral (Gr. oura, the tail ; L. sacrus, sacred, the sacrum). — A term applied to the ankylosed caudal vertebrae in birds. TJ'rostyle (Gr. oura, a tail; stulos, a style, pen). — A bony prolongation of the vertebral column in some fishes and amphibia. TTtero-gesta'tion (L. uterus, womb ; gestatio, the being carried in a litter). — The development of the embryo within the womb. U'terus (L. the womb).— The cavity in which the embryo remains during development. U'terus mascull'nus (L. male womb). — A portion of the male genital organs which in some Vertebrata represents the aborted uterus. 154 GLOSSARY. U'tricle ") (L. utriculus, a small bag). — The larger of the two TJtri'culus ) sacs of the vestibule of the ear. TT'tricle of male urethra (L. utriculus, a small bag). — Another name for the prostatic vesicle. TJ'vnla (L. a little grape). — The pendent body at the back of the soft palate ; also a small projection in the cerebellum. V. Va'cuole (L. vacua, I make empty). — A small clear space in a protoplasmic cell, and in the protoplasm of some Protozoa. Vagi'na (L. a sheath). — The passage by which the uterus communicates with the exterior. Applied also to the lower sheathing portion of the leaves of some plants. Vagi'na cellulo'sa (L. cellular sheath). — A name sometimes applied to the general external covering of nerve trunks. Vagi'nal arteries (L. vagina, a sheath). — The branches of the hepatic artery which supply the walls of the ducts, vessels, and Glisson's capsule of the liver. Vaginal plex'us (L. vagina, a sheath; plecto, I twine). — The nerves supplied to the vagina. Vagi'nal pro'cess (L. vagina, a sheath).— A process of the temporal bone. Vagi'nal syno'vial mem'branes (L. vagina, a sheath).— A term applied to those synovial membranes which form sheaths for the tendons. Vagi'nal veins (L. vagina, a sheath). — Small veinlets in the liver which return the blood from the fibrous coat of the liver to the branches of the portal vein. Va'gns (L. wandering). — The tenth cerebral, nerve, so called because of its wide distribution. Valle'cula (L. a little valley). — A fossa of the cerebellum. Also the fold of the derma in which the root of the nail is implanted. Val'vTilse conniven'tes (L. little winking valves). — The trans- verse permanent folds of the mucous membrane of the small intestine. Vas jiberrans (L. wandering vessel). — A long narrow tube lead- ing from the lower part of the epididymis, and terminating blindly. Vas de'ferens (L. bearing-to vessel). —The excretory duct of the testis. GLOSSARY. 155 Vas spirale (L. spiral vessel).— A small blood-vessel of the internal ear. Va'sa afferen'tia (L. afferent vessels). — The lymphatic vessels which enter the lymphatic glands. Va'sa ambulacra'lia ca'vi (L. hollow ambulacral vessels).— Di- verticula of the circular ambulacral vessel in the Ophiuridea. Va'sa bre'via (L. short vessels). — Small blood-vessels supplied to the stomach. Va'sa efferen'tia (L. efferent or carrying-out vessels).— Small vessels passing from the vascular network of the testicle to the epididymis. Also applied to the lymphatic vessels which pass out of the lymphatic glands. Va'sa lac'tea or chylffera (L. lacteal or chyle-bearing vessels). — The absorbent vessels of the small intestine. Va'sa rec'ta (L. straight vessels). — The straight vessels of the testicle which pass from the seminiferous tubules to the vascular network. Also small straight blood-vessels which lie between the uriniferous tubes of the kidney. Va'sa vaso'rum (L. vessels of the vessels). — The system of small blood-vessels which supply the coats of the arteries, veins, and lymphatics. Va'sa vortico'sa (L. vortex-like vessels). — Small veins of the choroid coat of the eye. Vas'cular (L. vasculum, a little vessel). — Having or belonging to vessels ; full of vessels. Va'so-mo'tor nerves (L. vessel-moving nerves). — Nerves derived from the sympathetic system, and governed by a vaso- motor nerve-centre in the medulla oblongata, which are supplied to the muscular coat of the small blood-vessels. Va'so-peritone'al ve'sicle. — A sac developed in the Holothuridea from the archenteron, and which subsequently gives rise to the ambulacral vessels and the peritoneum. Vas'tus exter'nus (L. vastus, enormous ; fxternus, external). — A large muscle of the thigh. Vas'tus inter'nus (L. vastus, enormous ; internus, internal). — A large muscle of the thigh. Vein (L. vena, a vessel containing blood). — A vessel which returns blood to the heart. Ve'liger (L. velum, a sail; gero, I bear).— A term applied to the embryo of some Mollusca, which is provided with a richly ciliated disc-like body. Velum (L. a sail).— The ciliated disc-like fold of the inte- gument with which some embryo Molluscs are provided. 156 GLOSSARY. Ve'lum interpo'situm (L. the interposed veil). — A term applied to the choroid membrane of the brain which is situated between the fornix and optic thalami. Ve'lum medulla're ante'rius (L. anterior medullary veil). — Another name for the valve of Vieussens of the brain. Velum pen'dulum pa'lati (L. the pendulous veil of the palate). — The posterior part of the soft palate. Velum, poste'rior medullary (L. velum, a curtain).— A lami- nated structure in the cerebellum comparable to the valve of Vieussens. Ve'na a'zygos ma'jor (L. the great unyoked vein). — A. vein on the right side of the body, commencing in the lumbar region, and emptying itself into the superior vena cava. Ve'na ca'va (L. hollow vein).— The name of each of the two large veins which bring the blood back to the right side of the heart ; the vena cava superior bringing the blood from the head and upper extremities, the vena cava inferior returning blood from the trunk and lower extremities. Ve'na cor'dis mag'na (L. the large vein of the heart). — The large vein which returns the blood from the substance of the heart to the right auricle. Ve'na hemia'zygos (L. half-unyoked vein).— The smaller azygos vein ; a vein which, commencing on the left side of the trunk, answers to the large azygos vein on the right side, into the upper part of which it opens. Ve'na par umbilicalis (L. equal umbilical vein). — A small vein which sometimes opens a connexion between the external iliac and the portal vein. Ve'na por'tae (L. the vein of the gate, or portal vein). — The large vein which carries' venous blood, (derived from the stomach, intestines, spleen, and pancreas,) to the liver ; so called because it enters the porta or gate of the liver. Ve'na salvatel'la. — A name formerly given to a small vein by which the posterior ulnar vein commences. Ve'nse abdomina les anterio'res (L. anterior abdominal veins). — Large branches of the iliac veins which in the Reptilia run along the anterior wall of the abdominal cavity. Ve'nae advehen'tes (L. vena, a vein ; advc/io, to carry to a place). — Small veins which in the foetus carry blood into the liver from the ductus venosus. Ve'na ba'sis vertebra'rum (L. veins of the bodies of the verte- brae).— The veins contained in the canals within the bodies of the vertebrae. GLOSSARY. 157 co'mites (L. companion veins). — A term applied to two or more veins running in company with an artery. Ve'nae cor'dis mi'nimaB (L. small veins of the heart).— The small veins which return the blood from the substance of the heart. Ve'nse Ga'leni (L. veins of Galen).— Two veins formed by the union of branches from the choroid plexus of the brain. Ve'nae par'vse (L. small veins). — A number of small veins, com- mencing upon the anterior surface of the right ventricle, and passing separately into the right auricle of the heart. Ve'nse revehen'tes (L. vena, a vein; reveho, to carry back). — Small veins which in the foetus return blood from the liver to the ductus venosus. Venesec'tion (L. vena, a vein ; seco, I cut). — The process of bleeding or blood-letting by opening a vein. Ve'nter of scapula (L. venter, the belly ; scapula, the shoulder- blade). — The fossa on the anterior surface of the scapula. Ven'tral (L. venter, the belly). — Towards the belly; opposite to dorsal. Ven'tricle (L. ventriculus, a little belly). — The name given to the chambers in the heart which discharge the blood into the arteries, and also to certain cavities in the brain. Ventri'culus (L. a little stomach or belly). — The cavity of the " cup " in the Porifera. A part of the alimentary canal in insects. Vermi'cular (I,, vermis, a worm). — Worm-like. Movement in waves, such as are seen in the movement of a worm. Ver'mis (L. a worm). — The median division of the cerebellum. Ver'tebra (L. verto, to turn).— The name of each of the bony segments of which the spinal column is made up. Ver'tebra denta'ta (L. toothed vertebra). — Another name for the second cervical vertebra or axis which possesses the odontoid process. Ver'tebra pro'minens (L. prominent vertebra). — A name some- times given to the seventh cervical vertebra in man, on account of its prominent neural spine. Ver'tebrata (L. vertebra, a bone of the spinal column). — The great division of the animal kingdom, comprising all those animals possessing a vertebral column. Veriunon'tanem (L. verus, true; mons, a mountain). — The prominent fold of the mucous membrane in the prostatic portion of the urethra. Vesi'ca urina'ria (Latin).— The urinary bladder. 158 GLOSSARY. Ve'sicle (L. resitufa, a little bladder). — Applied to any small bladder-like body, as the umbilical vesicle which contains the food yolk. Ve'sico-u'terine folds. — Folds of peritoneum extending from the uterus to the urinary bladder. Vesi'cula prosta'tica (L. the prostatic vesicle). — A small body in the prostate gland considered to be a rudimentary uterus ; called also sinus pocularis. Vesi'culse seminales (L. seminal vesicles). — The receptacles of the semen, in which it lies for a longer or shorter period before being discharged. Vestibule of the aorta (L. vestibulutu, an entrance).— A small cavity in the ventricle of the heart adjoining the root of the aorta. Vestibule of the ear (L. vestibiilwn, an entrance). — The part of the labyrinth of the ear into which the semicircular canals open. Vestibule of the vul'va (L. vestibulum, an entrance).— The angular interval between the nymphse. Vestfbulum (L. an entrance). — The chamber in the Polyzoa into which the gullet and anus open. Vexillum (L. a vane). — The shaft of a bird's feather ; also the large uppermost petal at the back of a papilionaceous flower. Vibra'cnla (L. vibrare, to quiver). — Whip-like appendages with which the cells of some Polyzoa are provided. Vibris'see (L. vibro, I shake). — The hairs growing inside the nostrils ; so named because they vibrate when we breathe. Vrdian artery. — A small branch of the inferior maxillary artery which occupies the Vidian canal. Vrdian canal.— A small canal in the internal pterygoid plate of the sphenoid bone. Vfdian nerve. — A small nerve occupying the Vidian canal. Vil'lus (L. villusy shaggy hair). — A conical projection of the mucous membrane of the small intestine, containing blood- vessels and lacteal s. Vin'cula accesso'ria ten'dinum (L. vinculum, a fetter ; accessio, an increase). — Accessory fibres of the sheath of the flexor tendon of the fingers. Vis a fron'te (L. force in front). — A pulling force by which the flow of a fluid is assisted, as in the ascent of the sap in plants, where evaporation from the leaves acts as a vis afronte. GLOSSARY. 159 Vis a ter'go (L. force behind). — A pushing force by which the flow of a fluid is assisted, as in the ascent of the sap in plants, where the absorption of moisture by the spongioles of the rootlets assists in pushing on the sap in its upward course. Vlsnervo'sa (L. nervous force). — A term applied to signify the property of nerves whereby they conduct impressions. Vis'cera (L. the entrails). — Applied to all the organs contained within the body. Vis'cus (L. viscus, the inside of the body). — Any internal organ of the body. Vitella'rium (L. vitellus, yolk of an egg).— A gland which in some Turbellaria is connected with the female generative organs, and secretes a special yolk-like material. VitellFgenous cells (L. vttellus, yolk ; Gr. gennao, I produce). — Cells, secreted by the ovarioles of some insects, which probably supply nutriment to the growing ova. Vi'telline duct (L. vttell'us, yolk). — The duct by which in early foetal life the yolk sac communicates with the embryonic sac of the ovum. Vi'telline mem'brane (L. v;tellus, yolk). — The membrane which encloses the yolk of the ovum. Vitellus .(L. yolk of an egg). — The general contents of the ovum. Vit'reous (L. vitrum, glass). — The name given to the humour which occupies the posterior chamber of the eye, on account of its glassy appearance. Viviparous (L. vivo, I live ; pario, I bring forth). — Applied to those animals which bring forth their young alive. Velar artery (L. vola, the palm of the hand). — A branch of the radial artery distributed to the hand. Vo'mer (L. a ploughshare).— A bone of the skull, so named because of its fancied resemblance to a ploughshare. Vulva.— A general term for all the external parts of the female generative organs. W. Willis, circle of. — Anastomosis of the branches of the vertebral and internal carotid arteries in the skull. Wolffian bodies.— Temporary organs in the foetus from which the urinary and reproductive organs are developed. l6o GLOSSARY. Wormian bones. — Bones frequently found in the sutures of the skull. X. Xan'thocroi (Gr. xanthos, yellow, auburn ; chroma, colour). — A group of the human race which includes the Slavonians, Teutons, Scandinavians, and fair Celts. Xiphiplas'tron (Gr. xiphos, a sword ; plastos, moulded, formed). — The fourth lateral piece of the plastron in the Chelonia. XTpbisternum (Gr. xiphos, a sword ; stemon, the breast). — The posterior portion of the sternum, also termed in man the ensiform cartilage. XTphoid cartilage (Gr. xiphos, a sword ; eidos, shape).— Sword- like. Applied to the xiphistennun. Xiphosu'ra (Gr. xiphos, a sword; oura, a tail).— An order of the Crustacea only represented at the present day by the king-crabs, which have long sword-like tails. Zoan'thodeme (Gr. zoon, an animal ; anthos, a flower). — The whole group of zooids in the Actinozoa produced by the budding of a single polype. Zo'ea (Gr. zoe, life). — The larval form of some Crustacea. Zo'na dentl'culata.— Toothed belt. Zo'na glomerulo'sa (L. zona, a girdle ; glomcrosus, to make into a ball). — The outer layer of the cortical part of the supra- renal bodies. Zo'na orbicula'ris (L. orbicular zone). — A thick broad band of circular fibres in the capsular membrane of the hip-joint. Zo'na pectina'ta. — Comb-like belt. Zo'na pellu'cida (L. bright transparent belt). — The membrane enclosing the yolk of the unimpregnated ovum. Zo'na reticula'ris (L. net-like belt). — The inner layer of the cortical part of the supra-renal bodies. Zona'ria (L. zona, a maiden's girdle, belt). — A division of the Mammalia, so called from the shape of the placenta. 2o'nula of Zinn (L. little belt of Zinn). — The folded zone formed by the suspensory ligament of the lens of the eye. Zooglae'a (Gr. zoon, an animal; glia, glue).— The term applied to the resting, motionless stage of the Bacteria, in which they are embedded in gelatinous material. GLOSSARY. l6l Zb'oid (Gr. zoon, an animal ; eidos, shape). — A term applied to each of the individuals which make up a compound organism. Zo'ology (Gr. zoon, an animal ; logos, a discourse).— The branch of Biology which treats of animal life. Zo'ophyte (Gr. zoon, an animal ; phuton, a plant). — A term sometimes applied to animals which resemble plants, such as corals, sea-anemones, sponges, &c. Zo'ospores (Gr. zoos, alive; spora, a seed). — The name given to spores which are provided with cilia, and are therefore capable of spontaneous movement. Zo'otomy (Gr. zoon, an animal ; temno, I cut). — The art of dissecting animals. Zygan'trum (Gr. zugos, a yoke ; antron, a cave). — A fossa on the posterior face of the arches of each of the vertebrae of the Lacertilia, into which the zygosphene of the succeeding vertebra fits. Zygapo'physis (Gr. ziigos, a yoke; apophuo, I grow). — The yoke-pieces or articulations of the vertebras. Zygocar'diac os'sicle (Gr. ziigos, a yoke ; kardia, the stomach). — The name of each of a pair of pieces in the skeleton of the stomach of some Crustacea. Zy'goma ") (Gr. zugos, a yoke). — The arch formed by Zygoma/tic arch ) the malar bone and the zygomatic process of the temporal bone of the skull. Zygoma/tic fos'sa.— -The lower part of the fossa bridged over by the zygomatic arch. Zygoma'tici muscles. — Two muscles {major and minor) arising from the zygomatic arch. Zy'gosphene (Gr. ziigos, a yoke ; sphen, a wedge).— A process on the anterior face of each of the vertebral arches in the Lacertilia, which articulates with the zygantrum of the preceding arch. Zy'gospore (Gr. ziigos, a yoke ; spora, a seed).— A spore pro- duced by the union of buds from two adjacent hyphai in the process of conjugation by which some fungi multiply. lllllllilllllli fllfil 01533 5720" UC SOUTHERN REGIONAL LIBRARY FACILITY A A 001 435 322 1