28 ARTHUR BOLLES LEI 
tightly-folded V’s.t. And this is also doubtless the case with the 
very short thick chromosomes of the Hemipteron Pentatoma 
(Carpocoris) nigricornis. 
We find, then, that in the nuclei we have been studying the 
chromosomes become doubled at the telophase, or before, 
through a folding-in of their limbs. This brings 
those limbs into a state of parasyndesis or close juxtaposition 
throughout their length, so that little change (other than the 
elongation due to their growth during the interphase) is required 
in order to bring them into the state in which they are found 
at the commencement of the spireme stage. This is illustrated im 
figs. 55 to 59. But this process is perhaps not followed exactly 
in all nuclei. I have evidence that the folding, or at all events 
the definitive parasyndesis, of the limbs may be deferred, and 
' In the Orthoptera the folding takes place not only as early as the early 
anaphase, but sometimes as early as the equatorial phase. In the equa- 
torial figures shown in figs. 60 (Oedipoda cothurna) and 63 
(Decticus verrucivorus) all the chromosomes are tightly folded 
into the stave shape. The same is the case in Oedipoda germanica, 
Oe. coerulescens, and Oe. (Mecostethus) parapleura. In 
Gomphocerus rufus the majority of the chromosomes appear in the 
stave form; but there may be some open V’s. In Stenobothrus 
biguttulus I suspect that the equatorials have always exactly two 
large chromosomes of the open V shape, all the others being tightly folded 
into the stave shape. It is perhaps not rash to conclude that all the cases 
of chromosomes described by authors as straight rods with a terminal 
spindle insertion are in reality cases of tightly-folded V’s with an apical 
spindle insertion, 
Fig. 63 (Decticus verrucivorus) shows sixteen large autosomes, 
fourteen small ones, and a monosome, therefore thirty-one in all. This is 
as it should be: for in this species I find in all unobjectionable images 
either sixteen large autosomes and fourteen small, or fifteen large and 
fifteen small, and a monosome ; the difference resulting from the fact that 
it is sometimes difficult to decide whether a chromosome is an unusually 
small ‘large’ one or an unusually large ‘small’ one. Buchner (‘ Arch, 
Zellforsch.’, iii, p. 342, and fig. 82 of Taf. xix) correctly gives the number 
as thirty-one in all. Vejdovsky (op. cit., pp. 33 and 44), notwithstand- 
ing that he had this description before him, insists that there are only 
twenty-three in all, Reference to his figs. 65 to 69 shows that he has 
mistaken entire chromosomes tightly folded into the stave shape, and 
fortuitously approximated at their apices, for mere limbs of open V’s, 
