PARACOROTOCA AKEK.MANI (w'ARliEX). 



815 



wards, thickened, and provided on the inner surface with 

 numerous scale-like set^e which catch on a roughened surface 

 on the latero-dorsal edge of the raetathorax (PI. XVI, fio-. 19). 

 The relationship of the elytra to the abdomen and thorax is 

 shown by a series of sketches in text-fig. 1, and it will be 

 seen that the elytra constitute a supporting bridge which is 

 not liable to slip, and distributes evenly the weight of the 

 overlying abdomen. 



Alge.— The alte are small, irregularly puckered, mem- 



Paracorotoca akermani. Diagrams showing the relation- 

 ship of the elytra to the thorax and overlying abdomen. A. 

 Transvei'se section through anterior region of metathorax. B. 

 Through plane of metathoracic s^Diracle. c. Through anterior 

 region of abdomen. 



branous structures, in which there occur irregular pieces of 

 chitinous tubes or ridges ; these would appear to represent the 

 broken-up venation of the wings (figs. 3 and 27). The alee 

 are quite functionless and are more abortive thau in Ter- 

 mitomimus. They arise anteriorly at the junction of the 

 metanotum and metasternal episternite. 



Between the metasternal episternite and metanotum there 

 is a membranous body-wall, and posteriorly this is expanded 

 into a thin-walled backwardly directed pouch on each side. 

 These latei'al pouches lie alongside the abdominal stalk 

 (fig. 2). A similar structure, but less conspicuously de- 



VOL. 4, PART 2. 22 



