Lectures on the comparative anatomy and physiology of the invertebrate animals : delivered at the Royal College of Surgeons . Before, however, entering upon these results of later re-searches, let us see what Hunter was able, by the ordinary anatomicalprocedures, to demonstrate and leave for our instruction. In thesespecimensf, which belong to the genus Rhizostoma, he has insertedhis skilful injecting apparatus into the central cavity of the body {.fiO *^^^-> ^-^\ plunged, so to speak,in medias res, and made con-spicuous by his coloured injec-tion, both the extraordinary routeby which the n
Lectures on the comparative anatomy and physiology of the invertebrate animals : delivered at the Royal College of Surgeons . Before, however, entering upon these results of later re-searches, let us see what Hunter was able, by the ordinary anatomicalprocedures, to demonstrate and leave for our instruction. In thesespecimensf, which belong to the genus Rhizostoma, he has insertedhis skilful injecting apparatus into the central cavity of the body {.fiO *^^^-> ^-^\ plunged, so to speak,in medias res, and made con-spicuous by his coloured injec-tion, both the extraordinary routeby which the nutriment reachesthat cavity, and also the channelsby which it is distributed for thesupport of the general prolongation of the commoncavity a into the base of theproboscis {li) there divides intofour canals (c), which enter thebase of the four branches (/>, p),into which the proboscis branches again divide andsubdivide along their plicated bor-ders ; the nutrient canals followtliese ramifications, and terminate in numerous fringed pores ((/, tZ), * CXXXVII. p. 219. f Nos. 847. 982, 983. M 2. Khizostoma. 164 LECTURE IX. upon tlie ultimate ramifications at the margins and clavate ends ofthe proboscis. These pores are, in truth, the commencement of thenutritive system ; they are, in this respect, analogous to the numerouspolype-mouths of the compound coral zoophyte* ; but in the Rhizo-stome a common central sac is interposed between the ingestiveconduits and the vascular or chylaqueous system of the body. Minuteanimalcules, or the juices of a decomposing and dissolving largeranimal, are absorbed by these pores, and are conveyed, more or lessdigested in transitu, by the successively uniting canals to thecentral cavity. Digestion being completed, the chyle passes at onceinto the vascular system, which is in fact a continuation and rami-fication of the digestive cavity. The nutrient fluid, with sea-water,passes by vessels (e), which radiate from that cavit
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Keywords: ., bookauthorowenrichard18041892, bookcentury1800, bookdecade1850
