PLATE V. 



Figs. LXI-LX1I. Sections through the first and second maxilla. 



Fig. LXIII. Transverse section of an older embryo through the first maxillae. 

 It is closed dorsally by mesodenn; beneath this lie the blood cells. 



Figs. LX1V-LXV. Transverse sections of the thoracic region Body wall 

 completed dorsally by mesoderm ; the amnion is incomplete. 



Fig. LXYI. Longitudinal section of ovarian tube of fly; CB'-CB IV represent 

 sections of successive chambers of the tube. 



Fig. LXVII. Longitudinal section of a more advanced terminal chamber (C IV )- 



Fig. LXV1II. Longitudinal section of a more advanced terminal chamber (C' x ) 

 showing elongated epithelium (OVE) excreting chorion (CH) and germinal vesicle 

 (GV). 



Fig. LXIX. Transverse section of terminal chamber at same stage as pre- 

 ceeding through germinal vesicle (CV) and germinal spot (CS). 



Fig. LXX. A longitudinal section of terminal chamber showing germinal 

 vesicle (GS) without boundary. 



Fig. LXX'. Portion of same section more highly magnified. 



Figs. LXXI-LXXIV. Sections through the oesophageal region of a spider em- 

 bryo showing amniotic folds (AM) on each side of the supra-cesophageal ganglion, 

 the outer limbs of which in the most posterior section (Fig. LXXIV) have united. 



