Chap. I. 



METAMORniOSES OF ANIMALS. 



83 



investigations, extending over a variL'ty of families, so ninch needed, as in tliat of 

 Birds, tliough the general development of these animals is, perhaps, better known 

 than that of any other tj-pe;^ while the class of Mammalia^ has found in Bischoflf 



a most successful 



and thorough investigator.' 



kriito, Si)lotliiirn, 1841, 4to. fig. — Quuliiues observa- 

 tions sur rcmbryologie des Batraciens, Ann. Sc. n., 

 3e ser. vol. 2, p. 45. — Rkmak, (R..) Untcrsucluingcn 

 iiber die Entwirkelung dcr Wirbelthicre, Berlin, 18/J."», 

 fol. — Newport, (G.,) On the Impregnation of tlie 

 Ovum in the Amphibia, Philos. Trans. R. See, 18.51, 

 I., p. 109. — WiTTicn, (W. II. v..) Beitriige zur mor- 

 phologischen und liistologisehen Entwickelung der 

 Ham- und Gesclileehtswerkzeuge der nackten Amphi- 

 bien, Zeitseh. f. wiss. Zool., 1852, vol. 4, p. 12.'). — 

 Weinlani>. (D.,) Ueber den Bcutelt'rosch, Miiller's 

 Archiv, 1854, p. 449. — Wvman, (J.,) Observations 

 on Pipa americana. Am. .Jour. Sc. and Arts, 2d ser. 

 1854, vol. 17, p. 309. 



* Paxher, (Ciir. it..) Diss, sistens historiam 

 nietamorphoscos tjuam ovum incubatum prioribus 

 quinqne diebus subit, Wirceb. 1817, 8vo. — Beitriige 

 zur Entwiekelungsgescbichte des Huhnchens im Eie, 

 Wiirzb. 1817, fol. fig. — Baer, (K. E. v.,) Entwicke- 

 lungsgesehiehte, etc., vol. 1. — Dutrochet, (II.,) 

 Histoire de I'oeuf des Oiseaux avant la ponte. Bull. 

 Soc. riiiloni., 1819, p. 38. — Hunter, (.John,) Obser- 

 vations on Animal Development, edited and liis Illus- 

 trations of that process in the Bird described by R. 

 Owen, London, 1841, fol. fig. — Prevost, (.J. L.,) 

 Memoire sur le developpement du poulet dans I'oeuf, 

 Ann. Sc. Nat., 1827, vol. 12, p. 415. — Prevost, (J. 

 L.,) et Lebert, Memoires sur la formation des 

 organes de la circulation et du sang dans I'embryon 

 du Poulet. Ann. Sc. Nat. 3e ser. L p. 205 ; II. p. 222, 

 fig.; III. p. 90. — Baudrimoxt, (A.,) et Martin St. 

 Ange, (G. J.) Rechcrches anatoraiques et physiolo- 

 gique^ sur le developpement du foetus, Paris, 1850, 

 4to. — Meckel v. He.msbach, (II.,) Die Bildung der 

 fiir partielle Furehung bestimmten Eier der ViJgel, 

 etc., Zeitseh. f. wiss. Zool., 1852, vol. 3, p. 420. — 

 In no class are embryological investigations extend- 

 ing over a variety of families more needed than 

 in thai of Birds, if we should ever derive any 



assistance from the knowledge of their development 

 for their natural classification. 



' For the ])a|)ers relating to the fatal envelopes 

 and the placenta and also to the different systems 

 of organs or any organ in particular and for human 

 embryology generally, see Bischoff 's article " Ent- 

 wiekelungsgcschichte," in R. Wagner's Ilandworter- 

 buch der Physiologic, p. 807, where every thing that 

 has been done in this direction, up to the year 1843, 

 is enumerated. For more recent researches upon 

 these topics consult, also, MUi.ler's Archiv, Wieg- 

 man's Archiv, Siebold und Kolliker's Zeitseh. 

 f. wiss. Zool., Milne-Edwards, Ann. Sc. Nat., and 

 the Annals and Magazine of Nat. Hist., etc 



' Bischoff, (Th. L. W.,) Entwiekelungsges- 

 chichte des Kaninchen-Eies, Braunschweig, 1842^ 

 4to. fig. — Entwiekelungsgescbichte des Hunde-Eies, 

 Braunschweig, 1845, 4to. fig. — Entwiekelungsges- 

 ehichte des Meerschweinchens, Giessen, 1852, 4to. fig. 

 — Entwiekelungsgescbichte des Relies, Giessen, 1854, 

 4to. fig. — Prevost, (J. L.,) et Dumas, (J. A.,) De 

 la generation chez les Mammiferes, etc, Ann. Sc Nat. 

 1824, vol. 3, p. 113, fig. — Bo.ianus, (L.,) Observatio 

 anatomica de fcetu canino 24 dierum, etc. Act. Ac. 

 Nat. Cuv., vol. 10, p. 139, fig. — Coste, (P.,) Embry- 

 og^nie comparee, Paris, 1837, 8vo. Atlas 4to. — His- 

 toire particuliere et generale du developpement des 

 corps organises, q. a. — Rechcrches sur le generation 

 des ilammiferes et le developpement de la brebis, 

 Ann. Sc N.it., 1835, HI. p. 78. — Rechcrches sur 

 la generation des Mammiferes, Paris, 1834, 4to. fig. 

 — Bernhardt, (C. A.,) Symbola; ad Ovi Mamma- 

 lium historiam ante pregnationem, Vratisl., 4to., Miil- 

 ler's Areh., 1835, p. 228. — Barry, (M.,) Researches 

 in Embryology, Phil. Trans. R. Soc 1838, p. 301 ; 

 1839, p. 307; 1840, p. 529; 1841, p. 195. — Baer, 

 (H. E. V.,) q. a. — Owen, (R.,) On the Ova of 

 the Ornithorhynchus paradoxus, Phil. Trans. 1834, 

 J). 555. — On the Young of the Ornithorhynchus para- 



