Key to lettering
B.P. .. .. .. .. |
Birth pore |
E.S. .. .. .. .. |
Excretory system |
Ex. bl. .. .. .. .. |
Excretory bladder |
G.b. .. .. .. .. |
Germ ball |
G.c. .. .. .. .. |
Germ cell |
P.gl. .. .. .. .. |
Penetration gland |
P.gu. .. .. .. .. |
Primitive gut |