128 CHROMOSOMES IN THE SPERMATOGENESIS OF THE HEMIPTERA HETEROPTERA. 



losome pair was not visible (though it must be present on account of its division fore- 

 shadowed in the case shown in Fig. 223). 



Literature. — In my preceding account (1901?>) I did not find the diplosomes in 

 the sperraatogonic monaster, and did not describe the second maturation division ; 

 but I was correct in conchiding that there are one bivalent and two univalent diplo- 

 somes in the first maturation monaster. 



29.' CVMUS ANGUSTATUS Stal. 



My preparations showed neither spermatogonic mitoses nor pole views of the first 

 maturation division, and their staining was unsuitable for determining the phenomena 

 of the growth period. 



Second Maturation Division. — Pole views sh ow 14 elements, one of them ((/(. 1, 

 Fig. 226, Plate XII), very minute and probably a univalent diplosome. Lateral views 

 of the spindle demonstrate that one of the larger elements is composed of two bodies 

 of unequal size placed end to end {Di. 3, di. 2, Fig. 228) ; in one case these two lay 

 side b}'^ side (Fig. 227), and each seemed to be connected with only one spindle fibre. 

 This is probably a bivalent diplosome destined to undergo a reductional division. The 

 13 other elements would seem to divide equationally or at least into equal parts. 



While not much can be definitely decided from this stage alone, yet the phe- 

 nomena show similarity to those of PeliopeUa and Ichnodemus. That is, in the fii'st 

 spermatocyte there might well be 15 elements, one more than in the second ; and 

 these would be 12 autosomes that divide reductionall}', a small bivalent diplosome 

 dividing in the same manner, and a larger pair of diplosomes each component 

 of which would divide b}' itself and these two then conjugate in the daughter 

 cell. In the second spermatocyte there is certainly one bivalent element that divides 

 reductionally, and it shows close resemblance to the l^ivalent diplosome of the sanie 

 stage in Ichnodemus. 



Literature. — My preceding observations (I901t) stated nothing definite. My prep- 

 arations of Cym.us luridus, of which a brief description was given by me (li)Ola), 

 were not favorable for study. 



TINGITWv^. 



30. TiNGIS CLAVATA Stal. 



No sjiermatogonio divisions were seen. 



Grotrtli Period. — The iron-hiematoxylin stain of the sliiles was too deep for clearly 

 distinguishing allosomes, but, in addition to a large, somewhat irregular body that is 

 proV)ably a plasmosome, may be found one or two dense bodies of diflierent volumes 

 that may be diplosomes. 



