7<S Bulletin de la Société Entomologique cV Egypte 



only grow iniperceplihly dining the lai-al period. Thus 

 il is in a very sliorl lune alter llic nioull llud the unl'ol- 

 ding lakes plaee. 'J'lie grey grasshopper, Pdchijlijliis 

 c'z/}('/Y<.src7î.s-, is anolhei- ease in |)oinl. (Faiìiih, Sou\. l^^nl. 

 VI p. 21).'), 4lli ed. and Aheuis des Inseeles, p. 248). 

 Manlidae and some Aeiidiichie aie in lliis respeel 

 eoniparal)le lo Lei)i(hìi)lcra, Lil)elkdidae, and (lieadichie, 

 Tlie wing ii'.dinienls oC Lepidoplera (hlTer IVoni 

 Ihose of Manlichie in thai, during the larval period, 

 they are plaeed internally under the sUin of the 

 eaterpillar. (See (ionin, 1(S1)4). Alter Ihe last larval 

 nioull, the lour winglets ai)pear exlernally in the 

 nymph stage and like the legs and antennae are 

 pressed along the hody from Iront to rear. The i)res- 

 sure exerted hy the edges of the slit in the east skin, 

 whieh slit is naturally narrow, ohliges the various 

 appendages to slreleh themselves out. A liquid se- 

 creted by the skin of Ihe nymp>h forms in drying a 

 hard covering, (the chrysalis), which covers the appen- 

 dages and moulding itself on them shows their exact 

 shape. 'Ulis prevents ths growth of the rudiments of 

 the appendages, it is true Ihat the wing stumps con- 

 tinue to increase their area owing to Ihe folding pe- 

 culiar to Iheni. but their length does not alter. It is 

 therefore at the lime of the imaginai moult — rupture 

 of the chrysalis—, as in the case of Empusa, that the 

 unfolding takes jilace in a single opei-ation. 



V. The Circulation of the Blood Observed in the 

 Wing Nervures During their Unfolding, 



On May .'51 si. lUhS, I placed undei- the niicrosco[)e 

 a male Eiupnsd which having linished to moult, was 



