eS a 
| | Quart. Tourn. Maor-Sc. WE 38 NS F816 
1s. blastopore 
(lavval_anus) 
’ hlastopore. 
| 
2 
A 
‘stalk, 
(braeoval lobe). 
cB an 
B35) 
3 
= (8 
al ee 
ae) 
SS, 5 Oe 
CS Rieader 
SS, is 
o0G% 
 ] 
x 
x Re 
se 
3 Edwin Wilson Cambridge 
