ORTHOPTEROIDEA (PANORTHOPTERA) 



231 



smaller dorsoanal pouch (Fig. 152), the ventral pouch completely 

 fining the antenna. The dorsorostral portions of the two coelomic sacs, 

 shortly before blasto kinesis, approach each other; their median walls 

 fuse and thus form the anterior portion of the cephalic aorta which func- 

 tions as a blood-distributing apparatus. The median walls of the dorso- 



am 



Fig. 153. — Locusta. Cross section of mandibular segment of 75- to 80-hour embryo. 

 {am) Amnion. (W) Blood cells, {coel) Coelomic cavity, imd) Mandible, (suboesb) 

 Developing subesophageal body. 



anal pouch form the proximal part of the cephalic aorta; the lateral walls 

 form fatty tissue. The walls of the ventral pouch are converted into 

 antennary muscles. The antennary coelomic sacs are the largest in the 

 body and form, in addition to that mentioned above, the investment of 

 the pharyngeal ganglion and of the corpora allata. 



dc mes bl ^PS 



coel 



am 



Fig. 154. — Locusta. Cross section of first maxillary segment of 59-hour embryo, (avi) 

 Amnion, (bl) Blood cells, (coel) Coelomic cavity, (dc) Provisional dorsal closure, (ect) 

 Ectoderm, (eps) Epineural sinus, {mes) Median mesoderm. 



The intercalary coelomic cavities are first seen during blastokinesis 

 lying between the antennary and mandibular mesoderm. They are 

 very small and evanescent and soon disappear. Among the Pterygota 

 they have been described in but few forms. 



The mandibular coelom is first in evidence at 56 hours as a pair of 

 small cavities lying in the hollow of the mandibular rudiments. Cells 



