22, PAULINE H. DEDERER 
Throughout the growth period the nucleus contains many small 
non-chromatic bodies, in a pale flocculent nucleoplasm, but no 
trace of a spireme. Sections of Rothschildia jorulla eggs and 
Actias luna showed an essentially similar condition. 
The literature dealing with the condition of the chromosomes 
during the growth period contains a number of diverse results. 
In several groups of vertebrates and invertebrates the persist- 
ence of the chromosomes has been demonstrated by Griffin 
(99), Stevens (’04), Dublin (05), Marshall (07, 710), Rickert 
(02), Born (’94), Schockaert (’02), Winiwarter and Saintmont 
(08), King (08), and others. Deton (’09) found only a pale 
reticulum in the egg of Thysanozoon; nevertheless he believes, 
with Grégoire (’09) that, whatever the appearance, the chromo- 
somes persist autonomously up to the maturation divisions. On 
the other hand, evidence that the chromosomes disappear as 
such during the growth period, is given by the work of Carnoy 
and Le Brun (’99), Hicker (’95), Woltereck (98), Bonnevie 
(06), Popofft (07), Goldschmidt (’08), and Schleip (09). The 
latter found an interesting condition in Cypris; in one form the 
chromosomes may be traced throughout the growth period, in 
another they disappear. With the second group Philosamia 
cynthia is to be included, as the facts observed indicate a grad- 
ual disappearance of the spireme during the growth of the egg. 
3. LITERATURE ON THE EARLY DEVELOEMENT OF EGGS AND 
NURSE CELLS 
In this list are included only a few of the papers dealing with 
the various early stages in the growth of the eggs and nurse 
cells in insects. 
Lepidoptera. Doneaster (12) describes the early oogenesis 
in Pieris brassicae and Abraxas grossulariata. In Pieris, after 
the oogonial divisions, when 30 chromosomes are seen in the 
equatorial plate, the nucleus enlarges and forms a reticulum, 
followed suddenly by the synizesis stage, in which a chromatin 
nucleolus appears. In the ensuing stage, a broken spireme of 
14 separate threads is seen, the fifteenth element being repre- 
