MANTLE-GLANDS OF CHROMODORIS. 115 



The size relations make it clear that what might loosely be re- 

 garded as an adaptive over-production of repugnatorial glands 

 subsequent to injury, probably results, on the contrary, from (i) 

 the limited quantity of the repugnatorial precursor substances, 

 and (2) the fact that normally the development of new glands is 

 inhibited through the attraction (" drainage ") of these substances 

 by glands already established. This will also explain why in cases 

 where, for example, but 3, rather than 5, " glands " are present 

 on an undamaged mantle, the " glands " are in the former in- 

 stance individually larger. What it is that determines the num- 

 ber of glands originally formed, remains undiscovered ; they are 

 probably absent in all individuals of C. zebra less than I cm. long. 



CITATIONS. 

 Bergh, R. 



'98 Die Opisthobranchier der Sammlung Plate. Zool. Jahrb., Suppl.-Bd. 



(Fauna Chilensis, i te Bd.), pp. 481-582. 

 Crozier, W. J. 



'16 On the Immunity Coloration of Some Nudibranchs. Proc. Nat. Acad. 

 Sci., Vol. 2, pp. 672-675. 



'17 The Nature of the Conical Bodies on the Mantle of Certain Nudi- 

 branchs. Nautilus, Vol. 30, pp. 103-106. 



'iga Further Contributions upon the Natural History of Chromodoris zebra: 

 the Question of Adaptive Coloration. Anat. Rec., Vol. 15, p. 349. 



'igb On the Control of the Response to Shading in the Branchiae of Chro- 

 modoris. Jour. Gen. Physiol., Vol. I., pp. 585-591. 

 Loeb, J. 



'15 Rules and Mechanisms of Inhibition and Correlation in the Regenera- 

 tion of Bryophyllum calycinum, Bot. Gaz., Vol. 60, pp. 249-27-6. 



'i8a Chemical Basis of Correlation, I. Ibid., Vol. 65, pp. 150-174. 



'i8b The Law Controlling the Quantity of Regeneration in the Stem of 



Bryophyllum calycinum. Jour. Gen. Physiol., Vol. i, pp. 81-96. 

 Wood-Jones, F. 



'12 Coral and Atolls, xxiii + 392 pp., London [Reissue]. 



