348 



EMBRYOLOGY OF INSECTS AND MYRIAPODS 



A B 



Fig. 306. — Diacrisia. Proctodaeum (A) and stomodaeum {B) of 65-hour embryo. 

 {am) Amnion. {Ir) Labrum. (wes) Mesoderm, {vroct) Proctodaeum. {stom) Stomo- 

 daeum. (suboesb) Subesophageal body. 



Fig. 307. — Diacrisia. Cross section of head of 65-hour embryo. A, through man- 

 dibular segment. B, through labial segment, {am) Amnion; (t) inner, (o) outer, {amf) 

 Amniotic fold, {ect) Ectoderm, {gl) Hypostigmatic gland, {lb) Base of labium, {md) 

 Base of mandible, {mes) Mesoderm, {mge) Strand of mid-gut epithelium, {nc) Ventral 

 nerve cord, {neurg) Neural groove, {silkg) Silk-gland invagination, {splm) Splanchnic 

 mesoderm, {suboesb) Subesophageal body, {y) Yolk. 



;•»— mge 

 - -splm 



5?. itv '', , v' 



A-Silkg / 

 r -tr 



;i '._. •'./' — splm 

 " - -silkg 





A B 



Fig. 308. — Diacrisia. A, section through neck region. B, through mesothorax of 

 65-hour embryo, {am) Amnion, {mge) Mid-gut epithelial strand, (p) Leg. {silkg) 

 Silk gland, {splm) Splanchnic mesoderm, {tr) Trachea, {tr. i) Tracheal invagination. 

 {trich) Trichogen cell. 



