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.THE AMEBIC AX XATCBALlsr [Vol. XLV 



A melanistic mutation has also occurred, and a pure stock of 

 it was easily produced. 



A male appeared in the melanistic stock having gold and 

 yellow wings: ''In fact, the entire fly is conspicuously yellow. 

 This color proves to be sex-limited. Thus far it has appeared 

 only in the males." 



Professor Morgan lias undoubtedly uncovered some new and 

 interesting facts, and it is hoped that he will he able to discover 

 something concerning the underlying causes of these mutations. 



In Science, May 19, 1911, Loeb and Bancroft report experi- 

 ments on the production of mutants in Drosoph ila. They secured 

 four types of mutation; a dark form, a pink eye, a white eye, and 

 a short-winged form. The dark form and the pink-eyed form 

 occurred also in control cultures, and the authors think it is 

 probable that the white-eyed mutation originated before the 

 treatment. The short-winged mutants have appeared thus far 

 only in cultures treated with radium, but in only two out of sev- 

 eral hundred such cultures. The treatments used were high 

 temperatures, exposure to radium, and exposure to Roentgen 

 rays. Where mutations were obtained in the treated cultures 

 they occurred in only a very small proportion of the cultures, 

 and the authors appear to doubt whether or not the treatment 

 was responsible for the mutations. 



Professor Cockerell, in the Annals and Magazine of Natural 



esting ease in which apparently a female bee, in a genus 

 (Mcfjachilc) in which the female appears to be heterozygous for 

 the secondary sexual characters, with the female characters 

 dominant, has lost these secondary sexual characters and assumed 

 those of the male. He proposes a new genus (AndrogyneUa) 

 for this marked variation from allied forms. Cytologies! study 

 of these two related genera might reveal something of marked 



Professor Michael FMinv^ this' joumaf for 



May, 1911, under the title "Nucleus and Cytoplasm in Hered- 



tion I have seen of the relation of the various parts of the cell 

 to the phenomena of heredity. It is not necessary to review the 

 paper here in full, since it is available to the readers of this 

 journal. 



W. J. Spillman. 



