CHROMOSOMES IN THE SrERMATOGENESIS OF THE HEMll'TEKA HETEKOPTERA. 129 



Fird Miifunifloii Dlrision. — Pole views show in most cases 7 elements (Plate XIII, 

 Fig. 229), a circle of (J around a central one. On side view all of these appear dumb- 

 bell-shaped (Fig. 230) except the central one which is composed of parts of unequal 

 volumes {Di, di) ; these parts are placed usually end to end but sometimes side by side. 

 This central one is proltably a bivalent diplosome and divides reductionally, while 

 the G others are proljably bivalent autosomes that also divide. In two pole views out 

 of a considerable number seen cS elements were found; this happens because sometimes 

 the components of one of the au^;osomes may be separated, as the two bodies marked 

 71/ in Fig. 231. 



Second MaiuTQlion Division. — There are regularly 7 elements present, namely, 6 

 autosomes and either the larger {di, Fig. 232) or the smaller diplosome [Di, Fig. 233). 

 In a single case, manifestly an abnormality, 8 elements were present, both diplosomes 

 being in the same cell [Di, di, Fig. 234). All 7 elements divide, presumably equa- 

 tionally, and 7 elements are always present in the spermatids (Fig. 235), half of the 

 spermatids containing a division product of the larger and half of them a division 

 product of the smaller spermatid. 



Literature. — In my earlier description (1901o) I noted that one of the chromo- 

 somes of the first maturation mitosis is characterized " in having its two components 

 of very unequal volume," but I failed to follow its behavior in this and the following 

 mitosis. 



PHYMATIDM 

 31. Phymata sp. {P. wolffii Stal.l). 

 I can add little to my former account (19016), and find that the chromosomes 

 are too crowded in the second spermatocytes to be counted with precision. But in 

 the spermatogonium I now think there are 29 and not 30 elements as I had pre- 

 viously described, for one is much longer than any of the others (il/o. Fig. 237, Plate 

 XIII), and this I had originally counted as two. This unique chromosome was to be 

 seen in all three of the distinct pole views. Therefore there is a possibility that a 

 monosome is present in this species. 



, REDUVIWM 



32. ACHOLLA MULTISPINOSA dc G. 



Spermatogonic Division. — Pole views show exactly 32 chromosomes (Plate XIII, 

 Fig. 238), of which 8 are 4 minute pairs of diplosomes. 



Growth Period. — The 4 pairs of diplosomes can be recognized throughout the 

 growth period, and were described in some detail in my previous paper ; they lie on 



A. p. S.— XXI. N. 23, 7, '06. 



