944 CHARLES ZELENY 
opercular modification in the branchia which stands in the posi- 
tion of the future radimentary operculum. This process, how- 
ever, is not sufficiently rapid to gain the upper hand and cause the 
development of a functional operculum. 
LITERATURE CITED 
Brugs, C. T. 1904 The internal factors of regeneration in Alpheus. Biological 
Bulletin, vol. 6, p. 319. 
Emmet, V. E. 1908 The experimental control of asymmetry at different stages 
in the development of the lobster. Jour. Exp. Zool., vol. 5, no. 4. 
Moraan, T. H. 1904 Notes on regeneration. Biological Bulletin, vol. 6. 
Miuter, Fritz. 1864 Fir Darwin. pp. 76-77. 
PrzipraM, H. 1901 Experimentelle Studien iiber Regeneration. Archiv fiir 
Entw.-Mech., Bd. 11, 1901. 
1902 Experimentelle Studien iiber Regeneration. II. Arehiy fiir 
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1905 Die ‘Heterochelie’ bei decapoden Crustaceen. Archiv fiir Entw.- 
Mech., Bd. 19. 
1907 Die ‘Scherenumkehr’ bei decapoden Crustaceen. Archiv fiir 
Entw.-Mech., Bd. 25. 
Strockarp, C.R. 1910 The question of reversal of asymmetry in the regenerat- 
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Wiuson, BE. B. 1903 Notes on the reversal of asymmetry in the regeneration of 
the chelae in Alpheus heterochelis. Biological Bulletin, vol. 4, pp. 197- 
210. 
ZELENY, C. 1902 A case of compensatory regulation in the regeneration of 
Hydroides dianthus. Archiv fiir Entw.-Mech., Bd. 13. 
1905 Compensatory regulation. Jour. Exp. Zool., vol. 2, no. 1. 
