442 THE PARASITES OF THE TERMITES. 



extreme ranging from 0.015 mm. to 0.06 mm. in length. They usually appear 

 rectilinear and regularly undulant with from three to five or six waves. They 

 commonly remain stationary in position and undulate more or less rapidly, but 

 they often advance or recede with variable rapidity, and sometimes become quies- 

 cent. Occasionally they bend at an obtuse angle while continuing to undulate, 

 and sometimes they become zigzag. Mostly they wave with regularity, sometimes 

 irregularly, and occasionally the ordinary number of their waves is doubled. The 

 smallest individuals, 0.015 mm. in length, are straight, but in movement become 

 bent in the segment of a circle or become sigmoid. 



The vibrios move in all directions among their associates. Not unfrequently 

 numbers adhere together by one end and form radiating groups, as represented in 

 Fig. 38. 



ARTHROMITUS. 



Arthron, a .ioint ; mitos, a thread. 



Arthromitus cristatus. Plate 52, Figs. 28-34. 



Leidy. Proc. Acad. Nat. Sci., IV., 1849, 227. A Flora and Fauna within Living Animals, 

 Smithsonian Contributions, 1851, 34. 



The name of Arthromitus was originally given by the author to a supposed 

 undescribed genus of delicate filamentous plants, found growing within the intes- 

 tine of certain myriopods, Spiroholus marginatus and Polydesmus virginiensis, and 

 of the coleopterous insect Passalus cormitus. 



The characters of the genus Arthromitus are as follows: Plant in the form of 

 exceedingly fine delicate filaments, usually attached by an attenuated extremity 

 and growing isolated or in small divergent groups. Filaments always simple, 

 cylindrical, of uniform diameter, homogeneous, and inarticulate, or more or less 

 distinctly articulate, with the free end slightly expanded or narrowed, and rounded 

 or truncated. Articuli mostly cylindrical, with little difi"erence of length and 

 breadth, sometimes feebly keg-shaped, homogeneous. Spores mostly in a series 

 occupying the distal articuli, always single, oval or oblong, darkly outlined, trans- 

 lucent, and homogeneous. 



Among the profusion of parasites obtained from the small intestine of our 

 Termite almost always a number of filaments may be observed with the characters 

 above ascribed to Arthromitus. They are usually observed loose, and have been 

 probably detached from their points of growth. When attached they appear to 

 spring singly or in groups of several together from a granule or minute round disk 

 adherent to the epithelium of the intestine. 



