eCL
ICL
eBL
IBL
Fold stages
Germ bond
22t1°C: 60'
90'
140'
160'
197'
200' (205') 420'
907180'
1237130'
957200'
1007200'
707200'
1207200'
707200'
h
i
k
I
m
n
o
567L
1057L
1757L
937 L
957215'
/205'
2007L
FIG. 8. Experimental analysis of embryogenesis in Calliphora (after Nitschmann, 1961),
a-d = median sections of operation stages (eCl, 1C1, early and late cleavage; eBl, 1B1,
early and late blastoderm), e-g, u n n o r m a l mesoderm invagination and segmentation.
Development after pole cautery (h, k, destroyed region black), incomplete ligation
(1, s, t) or complete ligation (i, m, r); v =plan of prospective segments based on ligation
experiments during dorsal fold stage (u). Abbreviations: ABD DC, abdominal differentiation centre; AMN, amnioserosa; BF, border fold; CEPH DC, cephalic differentiation
centre; CER, cerebrum; H F , head fold; LABR, labrum; M, mandible; PROCT, proctodaeum; STIGM, stigma; STOM, stomodaeum. Other abbreviations as in Fig. 3. Eggs