194 



COMPAEATIVE ANATOMY. 



Bibliography. 



TiZDEiiANir, Anatomie der Rohreniolotlim-ie, des pomeranzenfarbigen Seestemes vmd Steiuseeigels. 

 Landshut, 1816. — Shakpey, Art. Echinodermata in Todd's Cyclopfedia. II. — Muileb, J., Anato- 

 mische Studien uber die EcMnoderma. Ai'Ch. f . Anat. u. Pliys. 1850. — The same, Die Erzeugung 

 von Schnecken in Holothurien. BerUn, 1852. — The same, TJeber den Ban der Echinodermen. 

 Abhandl. d. Berl. Acad. 1853.— The same, Sieben Abhandlungen iiber die Larven und Metamor- 

 phosen der Echinodermen. AVjhandl. d. Berl. Acad. 1848-55. — Saks, M., Oversigt of Norges 

 Echinodermer. Christiania, 1861.— Gkeeff, Sitzungsbei', d. Gesellsch. z. Beford. d. Naturw. zu 

 Marbm-g, 1871-76. — Teuscheb, K., Beitr. z. Anat. d. Echinodermen. Jen. Zeitschr. Bd. X. 



Asteroida : Foebes, Ed., A History of British Starfishes. London, 1841. — Mullee, J., and 

 Teoschel, System der Asteriden. Braunschweig, 1812. — Agassiz, A., Embryology of the Star- 

 fish. Contrib. to the nat. hist, of the U. S. Cambridge, 1864.— Hoefmann, C. K., z. Anat. d. 

 Asteriden. Niederl. Ai-ch. f. Zoolog. Bd. n. — Saks, G. O., On some remarkable.f orms of Animal 

 Life, n. Christiania, 1875. — Lange, Wilh., z. Anat. d. Aster, u. Ophiur. Morpli. Jahrb. Bd. II. 



Crinoida : Mulleb, J., Ueber den Ban des Pentacrinus caput medusse. Abhandl. d. Berl. Acad., 

 1844.— Thomson, W., On the Embryogeny of Antedon rosaceus. PhU. Trans. 1865, II. — 

 Caepentee, W. B., Researches on structure, etc., of Antedon rosaceus. Phil. Trans. 1866, — 

 Saks, M., M^moire pour sei-vir a la connaissance des Crinoides vivauts. Christiania, 1868. — 

 Peekiek, Ed., Eech. s. I'Anat. etc. des bras de la Comatula rosacea. Ai-ch. de Zoolog. ex- 

 periment. T. n. — GoTTE, Vergl. Entwickelungsgesch. d. Comatula rosacea. Arch, f . mikr. Anat. 

 Bd. XII.— LuDWiG, H., Morpb. Stud. (Crinoideen) . Zeitschr. f. wiss. Zool. Bd. XXVIII. 



Echinoida: Valentin, Anatomie du genre Echinus, 1841. — Hoffmann, C. K., Anat. d. Echineu 

 u. Spatangen. Niederl. Arch. f. Zool. Bd. I.— Agassiz, A., Revision of the Echini, P. 1-4. 

 Cambridge, TT.'S. 1872-73. — Loven, S., Etudes sm- les Echinoidt^es. Kongl. Svenska Vet. Acad. 

 Handl. Bd. XI.— Wyville Thomson, On the Echinodea, etc. Phil. Trans. 1874, P. II. 



Holothuroida : Qitatebfagbs, Anatomie der Synapta Duvernrea. Ann. sc. nat. U. xviii. — 

 DiNiELSEN, 0., og KoEEN, J., Bidrag til Holothm'iarun udviMings-historie in Fauna littoralis 

 Norvegia?. II. Bergen, 1856. — Bauk, Beitrage zor Natin-geschichte der Synapta digitata. N. A. 

 L. C. XXXI.— Semfek, C, Reisen in den Philippinen. Bd. II. 1. Holothurien.— Selenka, Z. Entw. 

 d. Holothur. Zeitchr. f. w. Zool. Bd. XXVII. 



General Form of the Body. 



§ 158. 



Tte morpTiological relations o£ the various divisions of tlie 

 Echinoderma to one another, and to the lower forms, are best 

 understood by a reference to their development. The larva, w^hich 

 arises from the ovum, has only two antimera (bilateral symmetry) 



Fig. 94. Larval forms seen from the side. A Larva of a Holothurian. JB Larva of 

 a Starfish (Bipinnaria-type) . C .D Vermiau larvas. o Mouth, i Stomach, a Anus. 

 V Praeoral band of cilia, which is independent in B, C, and D, but in A surrounds an 



oral tract. 



and agrees in all essential points with the larva of the A.nnelides. A 

 ciliated band either surrounds the oral surface, which carries the 

 mouth (cf. Fig. 94, A), or is divided into two circlets, one of which 

 bounds the prseoral, and the other the postoral region (B). The 



