: 



CIPOI.IN. 



CIRRIPEDIA. 



of a yellowish colour, and resemble mull oblong masses of jelly, my 

 be wen in the month of August on the leaves of the Vrrliutum 

 Tkapfu* Mul somo few other plants whi.-h they feud U|H.H. When 

 bout to assume the pupa state they inclose themselves in a little brown 

 phericml ooooon (less than an ordinarily aiced pea) formed of a tint in 

 ous substance, which in attached to t lie leaves of a plant ; in about n 

 week or ten days after thin the perfect insect makes it* appearance. 



The genu* Hfmiurinm differs chiefly from OOHIU in having the 



. Homewhat ovate, -.>metimcs depressed, and not covering the 



apex of the abdomen ; and the anterior tibim furnished with a minute 



hook at the apex. Gymturtnm Seccobtmgte is the only species found 



in tlib< country. 



Heeiixu may be distinguished from either of the two last-mentioned 

 by the rostrum being short and thick ; the thorax nub-cylindrical, the 

 elytra el.niK.it.-, nearly cylindrical, and covering the body; the tibia! 

 are armed with a hook at the apex. Three species of this genus are 

 found in England. M. temifylindririu in about one-eighth of an inch 

 in length, and of a blackish colour with ash-coloured pubescence. 



Tin- genus \iinode* has the antenna! rather long, the club large ; 

 rostrum elongate, slightly bent ; thorax conical ; elytra sub-ovate mid 

 humped ; the anterior tibia; unarmed. No specie* of this genus have 

 yet been found in this country. 



(Schonherr, Synonymia Irutctorum, Genera et Specie* Citrevr 

 livntdttm.) 



ciroI.IX. [MARBLE.] 



CIKC.KA, a genus of Plants belonging to the natural order 

 Oxayrarraf. The specie* are found in woods and shady places. They 

 have little whitish pink flowers, having a tubular superior calyx with 

 a 2-parted limb, 2 petals, 2 stamens, and an ovary with 2 cells, each 

 of which contains 1 erect ovule. The genus constitutes the type of 

 a section of Onayracert in a reduced state. The species are commonly 

 called Enchanter's Nightshade; but whatever supposed properties 

 may have given rise to this name are purely imaginary. 



C. Luteiiana has ovate leaves, subterete petioles, no bracteoles, 

 petals deeply emarginate, calyx hairy, ovary 2-celled, fruit broadly 

 obovate. It is found in woods and hedge-banks throughout Great 

 Britain, though not an abundant plant. 



C. alpina has ovate leaves, flat petioles and setaceous bracteoles, 

 a glabrous calyx, and 1 -celled ovary. It inhabits woods and thickets 

 in mountainous district*, and is a rarer plant than the lost. 



CIRC.ETtTS. [F.vi.cuxiDJB.1 



CIRCULATION OF THK BLOOD. As the blood is necessary 

 for the nutrition of all the tissues of the body and for the develop- 

 ment of the actions of its organs [BLOOD], it must be put in motion in 

 order to be borne to them. " In man and in all the higher animals 

 an apparatus is provided, partly for the purpose of originating an 

 impelling force to put the blood in motion, and partly for the purpose 

 of conveying the blood when put in motion to the different parts of 

 the body." 



The organ that puts the blood in motion is the heart ; the pipes or 

 conduits which distribute the blood to the different parts of the body 

 are the great vessels in connection with the heart. The course of the 

 circulation, which in all the higher animals is double namely, one 

 through the lungs, called therefore the Pnlmouic, or the Lesser 

 Circulation ; the other through the system, called therefore the 

 Systemic, or the Greater Circulation will be beat understood by an 

 examination of the heart and vascular apparatus by which the 

 circulation U carried on. [HEART.] In this place therefore it will be 

 sufficient to refer to the evidence by which it is proved that the 

 blood is really in motion. Dr. Southwood Smith, in his popular 

 work on the ' Philosophy of Health,' thus sums up the proofs that 

 the blood is a flowing stream, and that it constantly pursues a 

 regular and determinate course. 



" 1. With the microscope, in the transparent parts of animals, the 

 blood can be seen in motion; and if its course bo attentively observed, 

 its route may be clearly traced. 



The membranes termed valves are no placed as to allow of 

 the freest passage to the blood in the circle described ; while they 

 either altogether prevent, or exceedingly impede its movements in 

 any-othrr direction. 



" 3. The effect of a ligature placed around a vein and an artery, 

 and of a puncture made above the ligature in the one vessel and 

 below it in the other, demonstrates both the motion of the blood and 

 the course of it. When a ligature is placed round a vein, that part 

 of the vessel which is most distant from the heart becomes full and 

 turgid, on account of the accumulation of blood in it ; while the part 

 of the vessel which is between the ligature anil the heart becomes 

 empty and flaccid, because it has carried on its contents to the heart 

 ana it can receive no fresh supply from the body. When, on the 

 contrary, a ligature is placed round an artery, that portion of the 

 vessel which lien between the ligature and the heart becomes full and 

 turgid, and the other portion empty and flaccid. This can only be 

 because the contents of the two vessels move in opposite directions 

 from the heart to the artery, from the artery to the vein, and from 

 the vein to the heart At the same time, if the v-in ! punctured 

 above the ligature, there will be little or no loss of blood ; while if it 



be punctured below the ligature, the bl<xl will tinue to flow until 



the loss of it occasions death ; which could not be unless the blood 



were in motion, nor unless the direction of its course were from the 

 t he vein to the heart. 



"4. If fluids b* injected into the veins or arteries, whether of the 

 dead or tha living body, they readily make their way and fill the 

 vessels, if thrown in the direction stated to be the natural course of 

 the circulation; but they are strongly resisted if forced in the 

 opposite direction." 



The author concludes his account of the structure of the heart and 

 blood-vessels, and of the course which the stream of blood is ascer- 

 tained constantly to pursue, with the following reflect 



"Such is the description, and, with the exception of tin- lir.it proof, 

 such the evidence of the circulation of the blood in the human 

 pretty much as it was given by the discoverer of it, the illustrious 

 Harvey. Before the time of Harvey, a vague and indi-' 

 tion that the blood was not without motion in the body hod been 

 formed by several anatomists. It U analogous to the ordinary 

 by which the human mind arrives at discovery (chap, iii . p 

 that many minds should have an imperfect perception of an unknown 

 truth before some one mind sees it in its completeness, and fully 

 discloses it. Having about the year 1820 succeeded in completely 

 tracing the circle in which the blood moves, and having at that time 

 collected all the evidence of the fact, with a rare degree of philoso- 

 phical forbearance, Harvey still *i -1 than eigl 

 re-examining the subject and in maturing the proof of even- jxiint, 

 before he ventured to speak of it in public. The brief tract which at 

 length he published was written with extreme simplicity, clearness, 

 and perspicuity, and has been justly characterised as one of t i. 

 admirable examples of a series of arguments deduced from observa- 

 tion and experiment that ever appeared on any subject. 



"Contemporaries are seldom grateful to discoverer*. Mor. 

 one instance is on record, in which a man has injured IIH f..rtn. 

 lost his happiness through the elucidation and establishment of a 

 truth which has given him immortality. It may lie that there are 

 physical truths yet to be brought to light, to say nothing of m-w 

 applications of old truths, which, if they could lie announce 

 demonstrated to day, would be the ruin of the discoverer. It is 

 certain that there are moral truths to be discovered, expounded, and 

 enforced, which, if any man had now penetration enough to set 

 and courage enough to express them, would cause him to be regarded 

 by the present generation with horror and detestation. Perhaps 

 during those eight years of re-examination the discoverer of the 

 circulation sometimes endeavoured in imagination to trace the effect 

 which the stupendous fact at the knowledge of which he had 

 would have on the progress of his favourite science ; and, it may be, 

 the hope and the expectation occasionally arose, that the inestimable 

 benefit he was about to confer upon his fellow men would secure to 

 him some portion of their esteem and confidence. What miixt have, 

 been his disappointment when he found, after the publication ot' hi* 

 tract, that the little practice he had hod as a physician by degr. 

 off? He was too speculative, too theoretical, not practical. Such 

 was the view taken even by his friends. His enemies saw in In 

 nothing but indications of a presumptuous mind, that dared to call 

 in question the revered authority of the ancients ; and some of tin in 

 saw, moreover, indications of a malignant mind, that conceived and 

 defended doctrines which, if not checked, would undermine tli 

 foundations of morality and religion. When the evidence of the 

 truth became irresistible, then these persons suddenly turned round 

 and said that it was all known before, and that the sole merit 

 vaunted discoverer consisted in having circulated the circulation. 

 The pun was not fatal to the future fame of this truly great man, 

 nor even to the gradual though .slow return of the public conl. 

 oven during his own time, for he lived to attain the sun; 

 reputation." 



For on account of the circulating apparatus, see the i 



AllTKHY, CAl'II.I.AUV V I >-l I -. BLOOD Vl BLS, lll,\l;i. Vl.lN. The 



nature of the circulating fluid i" given under ISi.ixin. For the i 



of the discovery of the circulation by llurv. y, see the article ll.\nvi:v, 



Wn.i LUC, in the llisr. AM. Itio... Div. 



CIRCUS. [F.vu-oxin*.] 



CIHL BUNTING. [EMI.I.IU/A.! 



CIRKHIBA'RBA, a genus of Fishes of the family GoWoda and 

 section A en . Only one species of this g- 



discovered, and this is from India. It has a tentaculuui over .ah 

 eye and nostril, throe large tcntacula nt the end of the mn//] 



eight under the point of the lower jaw. These tentacula 



the chief ili.stinctiou between this genus and that of CViiitw, to which 

 it is closely allied. 



ciHKllh;i; \DA. | A, Mini*.] 



CIKKIIINfS. [G.imo.l 



CIRRHOBRANCHIATA. [DEXTALIUM.] 



CIKHIirs. (TK.MIRII..J 



CIItKI'PKDIA, or riRRHII'F.DA (Lepat of I.in; 

 ,.f Cnvier and Fernssac, Cirrhipcdes of Lamarck, Nematopodet of l>e 

 I'.lainvillc, ('impedes of Latrcille), a well-defined natural group of 

 Marine Invertebrate Animals, whose place in the system has occa- 

 sioned much doubt and diU'crcncii of opinion among zonlogi-' 

 the earlier times the most absurd stories were propagated and believed 

 in relation to one of the most common - t 



