1901.] NATURAL SCIEXCES OF PHILADELPHIA. 263 



pheral, compact, densely staiuiag body of dumbbell form (Pi. X, 

 fig. 5, the chromatin reticulum not shown in this figure). This 

 possibly represents a true nucleolus and a chromatin nucleolus in ap- 

 position, but this point could not be determined. Similarly I 

 could not ascertain whether the three small chromatin elements of 

 the maturation mitoses are chromatin nucleoli. 



3. Cymus luridus Stal. 



There were no spermatogouic mitoses in the two testes examined 

 of this Lygfeid. 



Pole views of the monaster stage of the first maturation mitosis 

 show fifteen chromatin elements of very varying volumes (fig. 6), 

 though one (N. 2 f) is always much smaller than the others and, 

 by analogy ■with many other Hemiptera, probably represents a 

 chromatin nucleolus. Lateral views of the same stage show that 

 all these elements are dumbbell-shaped, and so probably bivalent 

 (fig. 7 showing the smallest and four of the larger elements). All 

 these elements become transversely divided. 



In the growth period of the spermatocytes, preceding the 

 maturation divisions, the micleus contains a large true nucleolus, 

 very irregular in form and peripheral in position. There are also 

 found as many as four smaller, rounded bodies, two of which are 

 frequently mutually apposed; if these be chromatin nucleoli there 

 would be potentially two bivalent chromatin nucleoli in the resting 

 spermatocyte (four univalent ones), though apparently only a 

 single bivalent one in the maturation mitosis. 



This species has a larger number of chromatin elements in the 

 first maturation mitosis than does the closely similar G. angustatus, 

 which I have shown to possess only thirteen. 



4. Lygus pratensis Linn. 



The individuals of this species of Capsid were labeled by Dr. 

 XJhler, " Lygus 2)ratensis ya.v.;'" whether Dr. Uhler regarded them 

 as simply showing slight differences in color, or as a good geo- 

 graphical variety, I cannot say. In the two testes studied there 

 were no spermatogouic monasters. 



In the monaster stage of the first maturation division are found 

 eighteen chromatin elements (PI. X, figs. 8, 9), namely, sixteen 

 larger and two (^JS\ 2) much smaller; while in the monaster of the 

 second maturation mitosis (fig. 10) are present seventeen elements, 



