968 PROTOZOA AND OTHER ANIMALS 



nymphs of Z. angusticollis and Z. nevadensis, and about a sixth of the 

 weight of soldiers. In this fluid gut contents the Protozoa are about as 

 thick as they could possibly be. Hungate, by centrifuging, showed that 

 about half consists of fluid, half of organisms. The organisms are in 

 mass mostly Protozoa, but there are also a great many bacteria and 

 spirochetes. Lund (1930) estimated the number of Trkhonympha, 

 Strehlomastix, and Trichomonas in Zootermopsis as 54,000; but obvi- 

 ously this would vary greatly with the size of the termite. 



In Cryptocercus punctiilates the colon is enlarged to a relatively 

 greater degree than in termites, becoming "an immense thin- walled bag 

 completely filled with Protozoa" (Cleveland et al., 1934). There are 

 probably millions of flagellates in a single full-grown roach. 



Most species of these flagellates ingest particles of wood. None of 

 them possesses cytostomes. Ingestion is through the surface of the body. 

 In TrJchonympha wood ingestion has been described by Swezy (1923), 

 Cleveland (1925a), and Emik (MS). Ordinarily most of the 

 wood in the faunated portions of the hind-gut is enclosed in the cyto- 

 plasm of the flagellates. Cleveland (1924) stated that in Reticulitermes 

 jiavipes nearly all the particles of wood are taken into the Protozoa, 

 whereas in Zootermopsis he found many particles free in the lumen of 

 the gut. 



Bacteria and other flagellates are sometimes ingested by Trkho- 

 nympha collaris (Kirby, 1932b) and other flagellates of termites. This 

 predatory habit is more frequent in some species than in others; and 

 ingestion of other organisms occurs more frequently under the con- 

 ditions of filter-paper feeding. Yamasaki (1937b) observed D'me- 

 nympha in many T. agilis after oxygenation. Wood is, however, the 

 chief and usually the only material taken into holozoic forms. Lund 

 (1930) noted that when Zootermopsis was fed on cornstarch, many 

 Trichonympha and Trichomonas ingested starch grains. Trichomonas 

 and Hexamastix in Zootermopsis are, according to Cleveland, able to 

 use starch. Grains of rice starch were taken in by three of the hyper- 

 mastigotes in Cryptocercus, and had some food value for them; and 

 Monocercomonoides in the roach could make full use of starch (Cleve- 

 land et al. 1934). 



Some flagellates in termites are saprozoic and do not take in solid 

 particles. That is true of Strehlomastix in Zootermopsis, of Hoplo- 



