BACTERIA IOI 



as is a common mode of reproduction, or arthrospores, when the entire 

 organism appears to transmute to a resting stage or spore, or, the organ- 

 ism may pass to the amorphous or symplastic condition. There is 

 also a possibility of a union or " con junction" of cells suggesting the 

 functioning of gametocytes. 



In passing into the symplastic stage the cells passing through involu- 

 tion forms appear to form clumps and lose completely their individual- 

 ity of form and contents in a general mass of disorganized protoplasmic 

 debris. Presumably scattered throughout this mass exists what may 

 be recognized in protozoal forms, yeast cells, et cetera, nuclear centers, 

 for out of this more or less homogeneous unvarying background of 

 protoplasmic substance appear many lines resulting in modified forms 

 which pass on to forms similar to the original cellular forms from which 

 this amorphous mass was at first derived. 



. The form of Azotobacter upon which this life-cycle theory is based 

 may not be, of course, conclusive; however, Jones has confirmed many 

 of the findings of Lohnis and Smith in the case of Azotobacter but is 

 not ready to subscribe to all of their interpretations. Jones * claims, too, 

 that so far as other species of bacteria are concerned in this theory 

 of life-cycle, he has been unable to confirm Lohnis and Smith who 

 assert that in the forty-eight species studied, they find practically the 

 same developmental cycle. 



This subject is of so wide importance that it deserves much atten- 

 tion and study. 



RESERVE PRODUCTS.! Besides the grains of chromatin which we 

 have just been considering in bacteria are found other granulations 

 which do not show the characteristics of chromatin and which act as 

 products of nutrition. These granulations are characterized by the 

 reddish color which they assume with most of the aniline blue or violet 

 dyes, as well as with haematoxylin. These bodies, which are common 

 to the majority of the Protista, are metachromatic corpuscles. 



They are found in larger or smaller numbers according to the species, 

 the age of the cells, and the medium in which they are living. Some 

 bacteria contain few metachromatic corpuscles (B. radicosus, megathe- 

 rium, mycoides); others produce many (B. alvei, asterosporus, Sp. 

 volutans, Bact. tuberculosis and diphtheria). The metachromatic 



Mones, D. H.: Jour, of Bact., Vol. V, p. 325. 

 t Prepared by A. Guilliermond. 



