604 



ZOOLOGY 



SECT. 



or portion extending vertically downwards ; and two lateral parts, 

 the (jence, in front. The eyes are a pair of reniform black patches 

 on the sides of the head ; each is seen when examined with a lens 

 to be divided into a number of minute hexagonal areas or facets, 

 like those in the eye of the Crayfish. Borne in sockets just below 

 the eyes are the long, slender, highly mobile feelers or antenna, 

 each made up of a large number of small segments, the first three 

 being larger than the others. Internal to the base of each antenna 

 is a rounded white space the fenestra the nature of which is not 



B 



el 



Fiu. 408. Periplaneta oricntalis, male. A, dorsal view. B, ventral view x 2*. ab.l, 

 nli.:!, ab.9, ab. 10, first, second, ninth, and tenth segments of abdomen ; ant. antenna; ;~e. cerci; 

 '/. rlypens ; ex. coxa of third leg ; E. eye ; el. elytra ; ep. epicrauium ;/. fenestra ;je. femur 

 of third leg; hd. head; lg.ljg.2,lg.3, legs; l.p. labial palp; Ir. labrum-; mn. mandible; m.p. 

 maxillary palp ; p.p. style on ninth abdominal segment, internally to which a podical plate 

 is seen ; th.l (th. in B), th.2, tfi.3, segments of thorax; ti. tibia ; tr. trochauter; ts. tarsus; 

 w. posterior wing. 



known, but which may be an abortive representative of the simple 

 eyes or ocelli found in most Insects. 



Movably articulated with the lower or ventral end of the clypeus 

 is a broad plate, the labrum or upper lip (Fig. 499, Ibr.) overhanging 

 1li<>, aperture of the mouth. Below the genae and articulating with 

 tin- sides both of the epicranium and of the clypeus are a pair of 

 stout mandibles (Fig. 499, md., and 500, man.) which work hori- 

 zontally like those of the Crayfish ; their inner edges are divided 

 into a number of teeth. Behind the mandibles are a more flexible 



