120 Dr. 0. V. Molleiidorff on some 



suggestion tliat the capacity of each sex for the production of 

 nuptial changes is equal is shown to be correct, but the disparity 

 in the size and in the requirements of ova and testes accounts 

 for the existence of a larger surplus of material in the male. 

 'J'his surplus may be used up partly as energy, partly in the 

 production of the secondary characters — the growth of snout 

 and discoloration of skin. 



In my paper above alluded to I wrote of the deposition in 

 the skin of some of the products of the disturbed metabolism, 

 and I suggested that in the case of the females of dimor[)hic 

 species the excess of |iignient might be disposed of in several 

 Mays, as, for instance, in the pigmented eggs of birds. 'J'his 

 is markedly confirmed by Miss Newbigin's statement that 

 " in the river this |)igment disappears from the muscles, is 

 apparently in the female for the most part transferred to the 

 ovaiieSj and so to the ova, and in both sexes is to a smaller 

 extent deposited in the skin." 



Lastly, it is important to note that while the transference is 

 direct and unmarked by degeneration of the losing tissues, 

 some of the matter transferred {e. g. the phosphorus) may be 

 altered in the process — a fact which opens uj) enormous possi- 

 bilities in the case of pigmentation, inasmuch as it is easy to 

 imagine that the transference might in some cases be accom- 

 panied by unforeseen colour-changes or by the formation of 

 pigment de novo. 



Leeuwepruit, Orange River Colony, 



South Africa. 



24th August, 1901. 



XXII. — On some Questions of Malacoloyical Nomenclature *. 

 By 0. V. MoLLENDOUFF, Ph.D. 



Mk. Pilsbry, who discussed my former paper on this 

 subject t, is certainly right when he says that ''controversy 

 over names is a notoriously bai ren employment " ; but it has 

 been especially so in our case, because he does not apparently 

 read German, and has in consequence misunderstood and 

 misstatid several of my views. Jn order to put the case 

 fairly before the English-reading public, I may be permitted 



* [Mr. Pilsbry's paper and Dr. von Mol]oudorft''8 reply having been 

 placed before our readers, this di.scus.sion, so far as the ' Annals' is con- 

 cerned, may now be considered to be clu.'*ed. — Eds.] 



t " The Nomenclature of Eurnpciin Helices," Ann. & Mag. Nat. Hist. 

 (7j \iii. pp. 325-3:^9, 



