March 31, 1911] 



SCIENCE 



499 



It will be noted that the flies with miniature 

 wings are even more numerous in this genera- 

 tion than the normal flies. Their chances for 

 development are therefore at least equal. 



Balloon Wings. — Occasionally flies have ap- 

 peared, especially in the truncated winged 

 stock, with each wing swollen up into a bal- 

 loon or bladder filled with fluid. When these 

 become dry the walls collapse and form flat 

 plates that are carried at right angles to the 

 body. Some of these flies have been isolated 

 and have produced practically pure stock with 

 the character present in all of the individuals, 

 and this condition has been carried through 

 two generations. The flies are exceedingly 

 active and look like small X's running about 

 in the bottles. They can not of course fly. 

 They seem to be very sterile and produce only 

 a few offspring, but nevertheless I have more 

 than a thousand of these flies alive at present. 

 Albino Flies. — Several times flies have ap- 

 peared that failed to develop black pigment in 

 the body. The eyes were red, i. e., unmodi- 

 fied by the lack of body pigment. One of the 

 albinos had white eyes, it is true, but it arose 

 in white-eyed stock, so that the colorless eye 

 bore no relation to the absence of pigment in 

 the body. The wings of these albinos were 

 almost white with a faint brownish edge. The 

 hairs of the body were brown instead of black. 

 Although some of these flies lived for nearly 

 a week they left no offspring. When the nor- 

 mal fly emerges it lacks pigment except in the 

 eyes. 



Melanistie Flies. — In some of the crosses 

 between wild flies and those with miniature 

 wings there have appeared in the second gen- 

 eration some flies, males and females, with 

 black wings. The veins of the wings are 

 broad and conspicuous. Pure stock of these 

 flies was easily, and at once produced. The 

 dark color is not confined to the wings, but 

 the entire body is black. The type is clearly 

 a melanistie variation of Drosophila. Crossed 

 with wild stock the flies of the first generation 

 are intermediate in color between the black 

 and the normal type. The color does not seem 

 to be sex-limited in relation to the normal, so 

 far as the experiments have been carried. 



Yellow Wings. — A male appeared in the 

 black-winged stock with golden yellow wings. 

 In fafrt, the entire fly is conspicuously yellow, 

 and makes a striking contrast with his dark 

 companions. He was bred to his black sisters, 

 and gave only black flies in the flrst genera- 

 tion. These were inbred and have produced 

 233 black females, 137 black males and 76 

 golden-winged males. Evidently the color is 

 sex-limited in relation to the melanic type 

 from which it arose. The same, or a similar 

 mutation, has appeared again in a stock not 

 related to the flrst, except in so far as both 

 came originally from flies with miniature 

 wings. As yet only males have appeared. 

 These have given in the first generation 

 (when crossed to their normally colored sis- 

 ters) normal flies. 



Wingless Flies. — Occasionally flies appear 

 without wings, but this character is not in- 

 herited, as a rule, and is due to some difficulty 

 in unfolding the primordia of the wings. But 

 in some of the stock of truncated wings I have 

 obtained a considerable number of flies with 

 tiny scales in place of wings. In one culture 

 there appeared 11 flies with scales, instead of 

 wings, amongst 125 winged flies. Although 

 this stock is very sterile it seems not improb- 

 able that, in time, a wingless fly can be pro- 

 duced. 



T. H. Morgan 

 Columbia University 



TEE NATIONAL CONFEBENCE COMMITTEE 

 ON STANDABDS OF COLLEGES AND 

 ' SECONDARY SCHOOLS 



The fifth annual meeting of the National Con- 

 ference Committee on Standards of Colleges and 

 Secondary Schools was held at the rooms of the 

 Carnegie Foundation for the Advancement of 

 Teaching, 576 Fifth Avenue, New York, N. Y., on 

 Saturday, January 28, 1911. 



All the organizations which send delegates to 

 the conferences of this committee were repre- 

 sented, those in attendance being as follows: 



President George E. MacLean, The State Uni- 

 versity of Iowa, representing the National Asso- 

 ciation of State Universities. 



Headmaster Wilson Farrand, Newark Academy, 

 representing the College Entrance Examination 

 Board. 



