152 



BOTANICAL GAZETTE 



[august 



may even show that they have some 



remote, on such a oractical problem 



Summary 



i. The wheat haulm possesses two types of statocyte: (i) the 

 smaller containing movable starch grains, (2) the larger with one 

 movable crystal of calcium oxalate. Both occur only in the nodes. 



2. The rate of fall of the crystal is much greater , and the period 

 of migration considerably less than the corresponding quantities 

 for the starch grains. 



3. It is suggested that the nodes of the wheat are definite sense 

 organs, showing a high degree of evolutionary development, and 

 that future study of the reaction to gravity of the plant should take 

 them into account. 











Part of this investigation was carried out in the field and la bora- 

 y at Rothamsted Experimental Station, and I gratefully acknowl- 



J. Russell and members 



me 



University College 

 Reading, England 



LITERATURE CITED 



1. Darwin, F., Presidential address, Section K. Brit. Assoc. Report. 1904. 



2. Haberlandt, G., Physiological plant anatomy (Eng. translation). 1914 



3. Prankerd, T. L., On the structure and biology of the genus Hottonia 

 Ann. Botany 25:253-267. 1911. 



, Notes on multinucleate cells. Ann. Botany 29:599-604. 191 5 



4 



5 



6. 



Preliminary observations on the nature and distribution of the 

 statolith apparatus in plants. Brit. Assoc. Report. 1915. 



, On the movements executed by young fern fronds, with especial 



reference to geotropism. Brit. Assoc. Report. 1916. 









