. Amphioxus and the ancestry of the vertebrates [microform]. Vertebrates; Chordata; Fishes; Ascidiacea; Vertébrés; Cordés; Poissons; Ascidiacés. L'Tti 236 TIIK ASCW/.LVS. m m t l*r^^ ance, doubles up obliquely forwards to the left atrial chamber, into which it opens by the anus (Fig. 107). In the angle made by the outgoing intestine with the stomach, a blind diverticulum arises. It is at first a sim- ple coecum, but soon begins to branch (Fig. 105 C), and finally forms an arborescent growth embracing the in- testine (Fig. 107). This is the so-called pyloric gland, and it is probably homologous
. Amphioxus and the ancestry of the vertebrates [microform]. Vertebrates; Chordata; Fishes; Ascidiacea; Vertébrés; Cordés; Poissons; Ascidiacés. L'Tti 236 TIIK ASCW/.LVS. m m t l*r^^ ance, doubles up obliquely forwards to the left atrial chamber, into which it opens by the anus (Fig. 107). In the angle made by the outgoing intestine with the stomach, a blind diverticulum arises. It is at first a sim- ple coecum, but soon begins to branch (Fig. 105 C), and finally forms an arborescent growth embracing the in- testine (Fig. 107). This is the so-called pyloric gland, and it is probably homologous with the hepatic caecum of Amphioxus. Appcndiculayia. It is generally agreed among those who have a voice in the matter, that most of the pelagic Ascidians (Salpa, Doliolum, Pyrosoma) are highly modified forms, spe- cially adapted to a pelagic life, one of the results of which is that their repro- duction is marked by a complicated alternation of generations. It would, therefore, not assist us in our comparison with Amphioxus to describe these types. There is, however, one family of pelagic Ascidians, the Appendicularice, with re- spect to which there are two widely different opinions. The Appendicularize are pelagic, free-swimming As- < .^/. Unicellular glands ^.. cidiaUS, whoSC adult COndi- Gill-slits. //. Dorsal hood-like fold of. Fig. III. — Appendicularia {Fritil- lariti) ftircata, from the ventral surface. (After Lankkster.) integument. ;;/. Mouth. /. Tail. tion is SO far similar to the. 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 the original Willey, Arthur, 1867-1942. New York; London : Mcmillan
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Keywords: ., bookcentury1800, bookdecade1890, booksubjectfishes, bookyear1894
