Sept. 15, I9IS Soil Protozoa 527 



DEVEIvOPMENT OF PROTOZOA FROM DIFFERENT COMPOST SOILS 



As shown in Table VIII, the development of small ciliates, with 

 respect to amounts of soil and media, was practically identical with 

 the development in moist soil, as shown in Table VII. It is apparent 

 from Table VIII that more small and more large ciliates develop from 

 the less composted soils. In all inoculations of dried blood with the 

 10 and 20 per cent composts and for the larger amounts inoculated 

 from the 30 and 50 per cent composts the maximum number of flagellates 

 were present from the sixtieth hour to the fourth day. But with smaller 

 amounts of soil inoculations from the 30 and 50 per cent manure soils, 

 the maximum numbers appeared from the fourth to the seventh day. 

 In the case of dried blood there was little difference in the numbers 

 of flagellates developed from the different amounts of soil, while in 

 soil extract inoculated with the smallest quantities of soil the maximum 

 had not yet been reached at the end of the eighth day; hence, no compari- 

 son could be made. From the 30 and 50 per cent composts more flagellates 

 were developed in blood extract than from the 10 and 20 per cent 

 manures. Considering the numbers of organisms developed, on the 

 gram basis, with dried blood there were more than two hundred times 

 as many flagellates developed from i gm. as compared with 100 gm. 

 of soil. It is seen that the maximum number of all organisms developed 

 from the sixtieth hour to seven days in dried blood, while in the case 

 of soil extract the maximum numbers had not been reached for the 

 smaller soil inoculation when the experiment was concluded. 



DEVELOPMENT OF DIFFERENT TYPES OF PROTOZOA FROM THE SOIL 



Very many different types of large ciliates were developed. Of the 

 forms identified Paramecium sp. was probably the most common. Other 

 large ciliates which were noted were probably Encheyis pupa Ehrb., a 

 few individuals of Urolaptus musculus Ehrb., and probably Nassula ele- 

 gans Ehrb. The vorticellae were very numerous, appearing the fourth 

 day, and were present in some solutions throughout the period of 30 

 days. They were developed in dried blood and soil extract from both 

 moist and dry soils. Next in prominence was the Colpoda ciu:ullus 

 O. F. M., which was first recognized on the fourth day. Colpidium 

 colpoda Ehrb. was also quite common. Of the flagellates species resem- 

 bling Monas guiiula Ehrb. and Monas vivipara Ehrb. were the most 

 common. Bodos spp. were also very common. A few dimastigate 

 amoebae, apparently Am,oeba radiata Kelbs, were seen between the 

 fifteenth and twentieth day after inoculation. A species correspond- 

 ing to Peranem^ triehophorum, Ehrb. appeared in small numbers from 

 the eighteenth to the twenty-second day. Likewise a few organisms 

 resembling Trinema anchelys Ehrb. were observed. Very few amcebse 

 97209°— 15— 4 



