PAKASITIC rROTOZOA FOUXD IX S. AFRICA. 135 



were found, each containing- erytlirocytes, in a portion of the 

 caecnni of an apparently healthy pin- in -Tolianneshurg. ATo 

 ulcers were seen in the caecum and colon of the pig. _ 



Examination of the Ciliata in the liying- condition is most 

 important, in order to obtain a correct knowledge of their 

 delicate structures and proportions. Many of them, such as 

 Diplodinium and Entodiniiim, are very susceptible to change 

 of temperature below that of the vertebrate host. The cofding 

 produces retraction of cilia and distortion of parts. 



Spiroch.et.i;. 



Organisms belonging- to the Protistan g-roup Spirochrcfacea 

 have been found in the crystalline styles of the Lamellibranchs, 

 Mytilvs crenafus and Tapes coi'mf/afa. obtained at Three 

 Anchor Bay, Capetown. In the former (Mytilus) the speci- 

 mens of spirochetes that were measured were 60// to 100// in 

 leng'th and about Ifx in breadth, with acuminate ends. In the 

 latter (Tapes) the spirochetes were 40// to TO// long and about 

 I'bfj. broad, with rounded or slightly acuminate ends. Both 

 spirochsetes were of the S. halhianii type, showing a membrane 

 or crest, especially those of Tapes, wherein the parasite usually 

 had a few changeable or unfixed coils on its body. The MyUUis 

 spirochetes, in addition to being longer and thinner, possessed 

 more flexible bodies and were more rapid in movement than 

 those of Tapes. A diffuse nucleus of chromatin rods was present 

 in each parasite. The Tapes were rarely infected (1 in 15), 

 Vidiile the l\Ti/tdus were somewhat more often infected (T in 75), 

 the molluscs being' examined in March. 



A small, thin spirochete was found in the rectum of the 

 Muscovy duck already mentioned. The organism measured 

 10// to 15// long and had pointed ends. 



1 would especially thank the Director and Officers of the 

 \ eterinary Uesearcli Laboratory at Onderstepoort for valuable 

 material and facilities for work, and the Research Grant Board 

 lor a grant towards the cost of collecting some of the material 

 for this investigation. 



