. A textbook of invertebrate morphology [microform]. Invertebrates; Morphology (Animals); Invertébrés; Morphologie (Animaux). 106 I Ji\ VERTEBliATK MOIIPIIOLOGY. ! !1 â I ^>cpht posteriorly to end usually in oue or two cercnl jirocesses, uud anteriorly show n dilutatioii succeeded b- u more or less well-niiirked narrow region, the two giving rise to a head and neck. The body is covered upon the outside by a ciiticle, which may be smooth as in the genus Jchtluidinin, ov take the for-n of overlapping scales as in Cha'tonoim\Yh^. 95), sometimes bearing spine-like prolongations. Along the ven
. A textbook of invertebrate morphology [microform]. Invertebrates; Morphology (Animals); Invertébrés; Morphologie (Animaux). 106 I Ji\ VERTEBliATK MOIIPIIOLOGY. ! !1 â I ^>cpht posteriorly to end usually in oue or two cercnl jirocesses, uud anteriorly show n dilutatioii succeeded b- u more or less well-niiirked narrow region, the two giving rise to a head and neck. The body is covered upon the outside by a ciiticle, which may be smooth as in the genus Jchtluidinin, ov take the for-n of overlapping scales as in Cha'tonoim\Yh^. 95), sometimes bearing spine-like prolongations. Along the ven- tral surface two bands of cilia run from the posterior part of the head region almost to the hind end of the bodv, and in addition to these patches i)f cilia are found upon the ventral surface and on the sides of the head, some of which are undoubtedly sensory in func- tion. Beneath the cuticular covering lies the ectoderm in the form of a laver of i)rotoplaHm in which no cell outlines can be perceived, but which contains numerous scattered nuclei. A pair of longitudinal muscle-bands lie be- neath the ectoderm on the dorsal sur- face, and other bands traverse the coelom in anantero-posterior direction. Transverse and circular muscles are, however, absent. A distinct cadom is present, the greater portion of which is occupied, however, by the internal organs ; it is not lined with a i)eri- toneal epithelium, nor are any mesen- teries j)resent. The mouth is situated at the an- terior extremity of the body and opens into a muscular (esophagus {w), which opens in turn into the cylindrical stomach (/"). To this succeeds a short intestine opening to the exterior at the posterior extremity of the bodv. No blood vascular system is present, but the excretory sys- tem consists of a single i)air of much-convoluted tubes (nephv) -which terminute at one « closed ciliated "funnel". Fio. 9r). â C/i,ftoiiotus maxi- IIINH lafier Zklinka). Cff = IHTVt' ifJl'lgl
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Keywords: ., bookcentury1800, bookdecade1890, bookpublishernewyo, bookyear1896
