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STUDIES ON GREG ARINES— WATSON 



109 



protomerite and deutomerite and is black in transmitted light. The 

 nucleus is not visible in vivo. 



Cephalonts and cysts were not recovered from the host. 



A table of measurements in which all dimensions are given in 

 microns follows: 



Total length association „ _ 1110 1110 1080 1050 



Primite 



Length protomerite „ 100 100 100 90 



Length deutomerite „._ 450 450 440 410 



Width protomerite _...._ 130 130 110 110 



Width deutomerite 170 180 180 170 



Total length sporont 550 550 540 500 



Ratio 



length protom. : total length sporont...l :5.5 1 :5.5 1 -.5.4 1 :5.5 



width protom. : width deutomerite...l :1.3 1 :1.4 1 :1.7 1 :1.5 

 Satellite 



Length protomerite _ 70 130 80 70 



Length deutomerite ...- _. _ 530 430 440 480 



Width protomerite _ 130 130 130 120 



Width deutomerite _ _ 190 210 170 180 



Total length sporont 560 560 520 550 



Ratio 



length protom, : total length sporont... 1 :8 1 :4.3 1 :6.5 1 :8 



width protom. : width deutomeritc.l :1.5 1 :1.6 1 :1.3 1 :1.5 



This species and the Old World Gregarina hlattarum Sieb. of Blatta 

 orientalis are differentiated as follows: 



G. hlattarum G. illinensis 



Shape Irregularly cylindrical Very regularly cylin- 



drical 



Posterior end satellite Not well rounded, Well rounded always 



often pointed 

 Sarcocyte Very thick Thin except in proto- 



merite 



Shape protomerite of Flattened, wider at But slightly flattened, 



satellite base than elsewhere as wide at base as at 



1.7 times as wide as top, 1.5 times as wide 



at top, 2.5 times as as high 

 wide as high 



