. Text-book of zoology for junior students. Zoology. 1110 ]\vki;tkhi',atk animals. united toLjether by a wull-developed nervous , and are tlma brought into organic connection witli one another. The vast majority of tlie I'ljly^oa are , and thus assume a very plant-like appearance. There is one fresh-water type, how- ever (viz., Cristiitdla), in whicli the colony can creep al:iout upon a flattened base very like the fcjot of a slug. In tliis same form, also, alone of all the PoIijziki, there is not any outer covering or ectocyst to the poly|jides. The l-'iili/zou are paitly inhabi
. Text-book of zoology for junior students. Zoology. 1110 ]\vki;tkhi',atk animals. united toLjether by a wull-developed nervous , and are tlma brought into organic connection witli one another. The vast majority of tlie I'ljly^oa are , and thus assume a very plant-like appearance. There is one fresh-water type, how- ever (viz., Cristiitdla), in whicli the colony can creep al:iout upon a flattened base very like the fcjot of a slug. In tliis same form, also, alone of all the PoIijziki, there is not any outer covering or ectocyst to the poly|jides. The l-'iili/zou are paitly inhabitants of the sea and partly of fresh water, ami they are tlms iii\'iiled into two groups which, as a. ;. l.'!:;.-l. Fra^'iiiriil, ,,f Fhi^,-,, Irtuiml,,, ,âââ nl' tlic Si':i-iiiii(>i. iialiiviil size. 2. A silJ'4lr |â,ly|ililr (.I' I'lilkcrln, iu:i;, slHiwili;.^ (I iiTllliu' rmwil (if tc-utlicles. 3. A |«i|.\-].iiir or Lophnpii:! r nj^tu 11 :â HI, a IVrsl I-wal r r P( ilyzc HI, lli-lllv 111,11,'llilieil, sliiiwiii;.' I lie ,-sl sliaii-il nnwn ,,r imtiH-Irs: a Tciiticular crown ; ), Oullrt; 'â , ; J Iiitrstiiir ; .â AuHs; ;/(iiz^aiil ; ;, EiMlcicvft; / general ruli;, dilfcr from one another considerably in anatomical structure. In niost of the flesh-water I'hIiizok tlie tentacles are b jrne U| a cri'scentii' disc or stage (tig. \'.VA, 3), so that the crown of tentacles assumes tlie sha])e of a horse-shoe. In almost all the marine foi'ms, on the other hand, the tentacles (tig. , 21 are simply arranged in a ciicle. All the I'dIiiz'iii are hcrmaphroilite, each polypide being furnished with tin- Ti'proiliii-tive proper to the t\\'o sexes. The eggs are siiii|ily hbei' int:) the pei'ivisceral cavity, where they are. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble
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Keywords: ., bookcentury1800, bookdecade1880, booksubjectzoology, bookyear1885
