H. C. DELSMAN. “On 
a 
NS 
2222 
98501 Fa 
OAN 
Oa, 
EE 
SA Fm rk 
1 
905) 
or, 
JZ 
Fig. | 
Median section | 
RT 
N en 
eet 
\ 
Ais 
Fi 
Median section thro 
Proceedings Royal Aca 
| 
“ Di) 
Si 
wo Nie? 
Fig. 3. Rana esculenta. 
Median section through the egg of text fig. lc. 
OER | 
ED 
Res) 
PSS 
© 
bon 
1 
Y sos 
OT 
_=p.neur 
Fig. 7. Amblystoma tigrinum. 
Median section through the egg of text fig. 2d. 
ABBREVIATIONS. 
a. anus, (a) anal pit, ad. anal diverticulum of gut, arch. 
archenteron, bl. blastopore, can. med, medullary canal, Ap. 
cerebral plate, /.b. liver cove, mes. mesoderm, 7.p. neuropore, 
(n.p.) place of the future neuropore, p. meur. neurenteric pore, 
pl. med. medullary fold, pr. cer. praecerebral thickening of 
the ectoderm, ventr. mes. ventral mesoderm. 
