226 



SCIENCE 



[Vol. LVI, No. 1443 



phoreseent organs along the sides were in good 

 condition. One of the specimens was given to 

 the Boston Society of Natural History as a 

 mem'ber of the New England fauna; the other 

 was presented to the Museum of Comparative 

 Zoology at Harvard. The swordfish was taken 

 on the eastern border of the Georges Banks, a 

 little inside the 500 fathom line. From this it 

 would appear that the swordfish do descend to 

 considerable depths for their meals, and, from 

 the good condition of the specimens, it would 

 appear that they make a rapid transition from 

 the feeding grounds to the surface for the 

 after-dinner siesta. 



J. S. Kjngslet 

 2500 Cedae Street, 

 Beekeley, California 



EXPERIMENTAL TRANSFORMATION OF THE 

 SMOOTH-BLADDER OF THE DOG 



The essential difference between the pale 

 smooth muscle of the bladder and the red in- 

 voluntary striated muscle of the heart is de- 

 pendent upon the differential intensity of the 

 hydro-dynamic pressure to which the vesicular 

 and cardiac mesenchymal cells have been sub- 

 jected, respectively. By expei-imentally varying 

 the velocity of application and the intensity 

 of the intra-vesicular pressure, which causes 

 tension of the smooth bladder muscle, during 

 a period of eight weeks, to a point comparable 

 with that found in the heart the non-striated 

 bladder muscle is transformed histologically 

 into cross-striated muscle, and physiologically 

 into an organ manifesting rhythmieity as long 

 as the hydro-dynamic pressure stimulus is ap- 

 plied. 



Prom the dynamic or functional, embryo- 

 logical viewpoint the various muscles, smooth, 

 cardiac and skeletal represent differences in the 

 amount of work that has been done upon them 

 by the differential growing parts of the embryo 

 during the active periods of growth."^ The es- 

 sential difference then physiologically between 

 the various muscles is their capacity for work 

 which in turn is dependent upon the amount 

 of work that has been expended in their pro- 

 duction. The reason for the different degrees 

 of energy possessed by the types of muscle is 



purely an embryologioal bio-mechanical prob- 

 lem and corresponds to the differential amount 

 of optimum tension which these muscles have 

 experienced during their fonnative period be- 

 cause of a dominant energetic zone extrinsic 

 to the region of myogenesis. The evidence 

 presented by these experiments warrants the 

 conclusion that as regards cross-striated muscle, 

 function determines structure and not the re- 

 verse. 



The writer wishes to thank Dr. Charles R. 

 Bardeen, University of Wisconsin, for re- 

 cheeking the evidence leading to the above con- 

 clusions. 



Ebek J. Caeey 



Marquette Univeesitt Medical School, 

 Milwaukee, Wisconsin 



AN ALBINO MUTATION OF THE DEMA- 



TIACEOUS FUNGUS BRACHYSPORIUM 



TRIFOLII 



This fungus has been under study in culture 

 since October, 1919, when it was first isolated 

 from clover plants. A description was pub- 

 lished in Phytopatliology, October, 1920, and an 

 intensive culture study of the fungus has been 

 continued since that time. The cultui-es were 

 started from a single spore and have been kept 

 going as a pui'e strain ever since. 



The normal fungus is of the dematiaceous 

 type, with dark brown hyphse, forming in cul- 

 ture a very dense black mat on and in the 

 medium. 



On one of a series of cultui'es made early in 

 November 1921 there appeared, starting from 

 the point of inoculation, a sector of growth 

 which completely lacked the black-brown color 

 of the normal mat. A microscopic examination 

 showed that the mycelium and conidia of this 

 light-colored area were morphologically iden- 

 tical with those of the normal gi'owth of the 

 fungus, except for the lack of the dark brown 

 color. 



Isolation cultui'es were made of this albino 

 material by the isolation of sclerotia-like 



1 Carey, E. J., 1919-20, Journ. of Gen. Physiol, 

 (a) ii, 357; (6) iji, 61; (c) Anat. Record, 1920, 

 xix, 199. 



