192 GENERAL SYSTEMATIC BACTERIOLOGY 



bovine peripneumonia. The single species was named Asterococcus 

 mycoides. The genus may be characterized as follows: Pleomorphic 

 cells, appearing at different stages as cocci isolated and in chains, and 

 as rods and filaments variously branched and swollen, apparently as 

 involution forms resembling frequently the bacteroids of legumes, cells 

 extremely minute, almost ultramicroscopic. Non-motile. No spores. 

 Stain with difficulty, best with Giemsa. Growth in cultures only 

 in presence of serum or hemoglobin. Apparently the organism has not 

 again been seen or recorded. 



The genus was recognized by Buchanan (1918, p. 44) and included 

 in his subtribe Hemophilinae. 



Astrobacter. A generic name given by Jennings (1896, p. 312) 

 to an organism found in stagnant water near Rubingen by Coppen- 

 Jones. Slides stained by Loeffler's method to demonstrate the flagella 

 of Spirillum undula when examined were found to show the organism in 

 question. The original material had been lost, so that the entire 

 description is based upon observation of the mounted slides. 



A simple rod-like bacterium. Initial cell division is marked by a 

 bifurcation of the end of the rod, producing a Y-shaped form. The 

 split deepens, and others occur, making tri-radiate types with the rays 

 spreading at an angle of 120°. Four rayed forms with various angles 

 occur, as do also forms with as many as eight rays. The rays do not 

 appear to all lie in a single plane. In a few cases transverse constric- 

 tions of some of the rays were noted. Whether this genus has been 

 based upon any form which actually occurs in nature has not been 

 proved. It is entirely possible that the so-called organisms are arte- 

 facts of some type. Until there is a demonstration of the living organ- 

 isms the generic name Astrobacter Jennings may well be held in abeyance. 

 It has apparently never been recognized or used by other investigators. 

 It is definitely rejected by Erwin F. Smith (1905). 



Athiorhodaceae. A family of the order Rhodobacteria proposed by 

 Molisch (1907, p. 28) to include those forms that do not possess free 

 sulfur granules in the cell contents. The following genera, described 

 in the same work, make up this family: Rhodobacillus, Rhodobacterium, 

 Rhodocapsa, Rhodothece, Rhodococcus, Rhodovibrio, Rhodocystis, Rhodo- 

 nostoc, and Rhodospirillum. The organisms all develop in the presence 

 of light. They possess two pigments called bacteriopurpurin and 

 bacteriochlorin. 



The family name does not conform to the botanical code in that it is 

 not derived from the name of any one of the component genera. It is 

 made a synonym of Rhodobacterioideae by Buchanan (1918, p. 128). 



