A 
pe 
icva 
OE TOEEEND, 
Plate II. 
W; 
pe, 
See 
BIAS vi: 
@B5=, 
ada, 
…, 
e, 
Fig. 1 Rana esculenta, median section through the egg}of 
fig. 40a (p. 147) 
Fig. 2 Rana esculenta, median section through an egg as in 
fig. 405 (p. 147) 
Fig. 3 Rana esculenta, median section through the egg of 
fig. 40c (p. 147) 
Abbreviations : 
a. anus 
(a.) anal pit 
a. d. anal diverticulum of gut 
arch. archenteron 
bl. blastopore 
can. med. medullary canal 
jp, cerebral plate 
Lb. liver cove 
mes. mesoderm 
np. neuropore 
(n. p.) place of the future neuropore | 
p. neur. neurenteric pore NER 8 ES 
pl. med. medullary fold P 
pr. cer. praecerebral thickening of the ectoderm 
ventr. mes. ventral mesoderm 
Fig. 3. 
