INTRODUCTION. 37 



Host. Parasite. Seat. 



Pheretima elongata Rhynchocystis awatii . . Seminal vesicles. 



Rhynchocystis mamil- Seminal vesicles. 



lata. 



Stomatophora bulbifera. Seminal vesicles. 



Pheretima heterochseta . . . Nematocystis hessei . . . Seminal vesicles. 



Nematocystis lumbri- Seminal vesicles. 



coides. 



Grayallia quadrispina . Ccelomic cavity. 



Pheretima posthuma Monocystis bengalensis. Seminal vesicles. 



Monocystis lloidi Seminal vesicles. 



Monocystis pheretimi . . Seminal vesicles. 



Stomatophora diadema. Seminal vesicles. 



Dirhynchocystisglobosa. Seminal vesicles. 



HraUNDINEA. 



•Ozobranchus shipleyi Haemogregarina nicorise Body. 



Gephyeea. 

 Dendrostoma signifer .... Extreniocystis dendro- Ccelomic cavity. 



stomi. 



Technique. 



Methods for the examination and study of Protozoa are 

 a.dequately dealt with in such works as Prowazek and Jollos 

 (1921), Wenyon (1926), Hartmann (1928), Belaf (1928), 

 Oatenby and Cowdry (1928), Knowles (1929) and Hegner 

 and Andrews (1930). The principal methods followed in the 

 study of the Sporozoa are given here for the benefit of those 

 taking up the study of the group. 



Examination in the Living Condition. — It is always desirable 

 to make observations on the hving organisms in the first 

 instance. The specimens are mostly studied in a drop of the 

 natural medium or body-fluid of the host -animal in which 

 they are found. Any pressure of the cover -glass might cause 

 deformities, and this should be guarded against by including 

 in the preparation small bits of detritus or a hair which will 

 support the cover -glass. If it is intended to continue the 

 observations for some length of time, " cavity slides " may be 

 used. The drop of fluid containing the organisms should be 

 put on a circular cover-glass, the margin of which is smeared 

 with melted paraffin or Czokor's wax, and the cover-glass 

 inverted over the cavity. This will fix the cover-glass to the 

 shde and prevent evaporation. The wax is made by heating 

 together and mixing in a shallow tin provided with a lid 

 ■equal weights of bees-wax and Venetian turpentine. The 

 wax becomes a soHd mass when cool, and can be appHed 

 by placing the heated portion of a wire on the wax and then 

 passing it round the cover -glass or the slide. To study the 

 developmental stages and natural movements the slide should 

 be kept at the body temperature of the host when this is 

 a warm-blooded animal. 



