114 



ILLINOIS BIOLOGICAL MONOGRAPHS 



[324 



Measurements of a few associations 

 in microns are as follows: 



Total length association 590 



Primite : 



Length protomerite 60 



Length deutomerite - 230 



Width protomerite 150 



Width deutomerite _ 130 



Total length sporont .. 290 



Ratio 



length protom. : total length 1 :5 



width protom. : width deutomerite 1 :1.1 

 Satellite : 



Length protomerite 50 



Length deutomerite : 250 



Width protomerite _.. 110 



Width deutomerite 150 



Total length sporont _ 300 



Ratio 



length protom. : total length 1 :6 



width protom. : width deutomerite 1 :1.3 

 Diameter cysts 350 



with all dimensions expressed 



570 540 



70 

 200 

 140 

 140 

 270 



1:4 

 1:1 



50 

 250 

 130 

 180 

 300 



1:6 



1:1.4 



300 



50 



220 

 140 

 180 

 270 



490 



60 60 



210 210 



170 180 



150 150 



270 270 



40 

 180 

 120 

 170 

 220 



1:5.4 1:5.5 

 1:1.3 1:1.4 

 350 



440 



40 

 190 

 120 

 100 

 230 



1 :4.5 1 :4.5 1 :5.7 

 1:1.1 1:1 1:4.1 



50 

 170 



90 

 120 

 210 



1:4.2 

 1:1.3 



GREGARINA STYGIA Watson 



[Figure 206] 



1915 Gregarina stygia 



Watson 



1915:33 



This new species was taken from Ceuthophttus stygius (Scudder), 

 hosts found in an unused cistern on Dr. C. B. Davenport's grounds, at 

 Cold Spring Harbor, L. I. 



The infection was heavy, as many as five hundred parasites being 

 found in each of several hosts, and each of the twelve examined con- 

 tained at least a few parasites. The region of infection is the intestine. 



The sporonts are biassociative as adults. The longest association 

 measured 360/A. The sporonts are barrel shaped, the maximum length 

 recorded being 180/t and the maximum width 100/x,. The protomerite is 

 nearly hemispherical in the primite and is flattened in the satellite. The 

 deutomerite is widest at or in front of the middle portion. The satellite 

 is somewhat more slender than the primite and is of the same length or 

 a little shorter. The endocyte is dark tan in color, not very dense in 

 either deutomerite or protomerite, and the nucleus is easily visible in 



