THE GENUS ASCOCOCCUS 135 



(Winslow and Rogers, 1905) to suggest the restoration 

 of the genus Ascococcus. 



We have not had an opportunity of working upon these 

 forms in the laboratory. Further study of the literature, 

 however, has strengthened our opinion that they possess 

 such a peculiar complex of characters as to forbid their 

 inclusion in any other x of the established genera. It is 

 clear, in the first place, that Asc. mesenteroides is, in many 

 ways, allied to certain of the Paracoccaceae. Its cells 

 occur in pairs, or in chains made up of paired elements ; 

 and on media which do not contain sugar it grows in 

 small transparent colonies like those of the diplococci or 

 the streptococci. Like organisms of these two genera it 

 produces acid in various sugar media and grows best at 

 temperatures between 30 degrees and 37 degrees. All 

 these properties ally Asc. mesenteroides with the Paracoc- 

 caceae. On the other hand its saprophytic existence 

 and its power of forming relatively enormous gelatinous 

 growth-masses in saccharose and dextrose media, mark 

 it off very clearly from the genus Diplococcus and the 

 genus Streptococcus, 



The only resource seems to be the recognition of a 

 distinct genus, which shares the fundamental growth- 

 form, temperature optimum, and fermentative powers of the 

 Paracoccaceae but has also the acquired ability of forming 

 large masses in saccharine solutions. We originally 

 placed this genus with the Metacoccaceae, in view of its 

 vigorous power of growth and saprophytic habits. More 



