629 
1898-99.] Mr T. H. Bryce on Duplicitas Anterior. 
It is therefore in the early stages of development that the 
origin of duplicity is to be sought. It is one of the problems 
which modern biological thought has hunted back to the ovum 
itself, and there the secret must lie hidden, until we are in a 
position to explain the conditions determining the orderly rhythm 
of normal development, from which it is a departure. 
LITERATURE. 
i. Dareste, Production des Monstfuosities , etc., 1891. 
ii. Gerlach, Die Entstehungsweise der Doppelmissbildungen, 
1882. 
iii. Klaussner, F., Mehrfachbildungen bei Wirbeltheiren , 1882. 
iv. Bianchi, Moniter Z. Ital. Ann. 6, p. 126. 
v. Hoffman, E., Archiv. fur Mikro. Anat ., vol. xli. 
vi. Mitrophanow, Archiv. fur Entwick. Meehan ., vol. i. 
vii. Kaestner, Archiv. fur Anat., etc., 1898. 
viii. Laguesse et Bue, Journ. d? Anatomic , xxxiv., 1898. 
ix. Jablonowski, “Inaug. Dissertation,” Berlin, 1896. 
x. Kopsch, Verhand. der Anat. Gesellschaft , 1898. 
xi. Allen Thomson, London and Edin. Mon. Journal , 1844. 
xii. Bruckhardt, Archiv. fur Anat., 1888. 
xiii. Mitrophanow, Archiv. fur Entwick. Mechanik ., vol. i. ; 
Behand. Anat. Gesell., 1893. 
xiv. Hertwig, “Urmund und Spina Bifida,” Arc h. fur Mikros. 
Anat., Bd. 39, 1892. 
xv. 0. Schultze, Arch, fur Entwicik. Mechanik., vol. i. 
xvi. Cleland, Mem. and Memoranda of Anat., 1889. 
xvii. Chabry, Journal de V Anat. et de la Phys., xxiii. 
xviii. Driesch, Yarious papers in Zeitschrift f. wiss. Zool ., Mitth. 
a. d. Zool. Station, Naples, Arch. f. Entioick. Mechanik. 
xix. Morgan, T. H., Anat. Anzeiger, ix. and x., and various 
papers in Arch, filr Entwick. Mechanik. 
xx. Wilson, Anat. Anzeiger , vii. 
xxi. Eischel, Arch. f. Entwickelungs Mechanik., Bd. vi. 
xxii. Loeb, Arch . f Entwickelungs Mechanik., Bd. i. 
