268 PROCEEDINGS OF THE ACADEMY OF [Marcll, 



univalent chromatin nucleoli may remain entirely disconnected. 

 In this rest stage the nucleus contains also one or two larger, 

 irregularly shaped true nucleoli (fig. 19, N.) which are not 

 apposed to the chromatin nucleolus. 



Pole views of the monaster stage of the first maturation mitosis 

 (PI. X, fig. 20) show seven chromatin elements; and lateral views 

 of such cases show that all seven are dumbbell-shaped, and hence 

 bivalent. The smallest of these elements is the chromatin nucle- 

 olus (N. 2, figs. 20, 21), and, as is generally the case in Hemip- 

 iera, this divides in metakinesis before the chromosomes do. Of 

 the six chromosomes proper, one is always much larger than the 

 others (figs. 20, 21), and this one evidently represents the union 

 of the two largest univalent chromosomes of the spermatogonia 

 (in fig. 21 is shown, besides the chromatin nucleolus, X. 2, thi 

 largest chromosome and three of the five smaller cliromosomes) ; 

 and one chromosome is much smaller than the others, often little 

 larger than the chromatin nucleolus (this is the one lying nearest 

 to the largest chromosome in fig. 21). All these elements are 

 transversely divided in the metakinesis. Occasionally pole views 

 of the monaster stage of the first maturation mitosis show eight 

 chromatin elements instead of seven; this is due to one of the seven 

 bivalent elements having precociously divided into its univalent 

 components. In the second spermatocyte are regularly found 

 seven univalent elements. 



Corizus annulatus in its spermatogenesis thus shows a ver}' close 

 similarity to C. lateralis Say, previously described by me. 

 7. Harmostes reflexulus Say. 



The individuals collected at Woods IIolI were marked by Dr. 

 Uhler, '' Harmonies reflexulus Say, variety "; whether a geographi- 

 cal race was thereby intended I cannot say. 



Five testes were examined. Tlie whole process of spermato- 

 genesis seems exactly similar to that described by me previously 

 for individuals of this species from Pennsylvania. 



This is one of the Hemiptera with an uneven normal number of 

 ■chromosomes, there being found in the spermatogonia thirteen 

 chromatin elements, namely, two smaller chromatin nucleoli {N. 2 

 of figs. '11 and 23) and eleven larger chromosomes proper. The 

 uneven normal luimber of chromosomes being a relatively rare phe- 

 nomenon, it having been observed so far only in four species of 



