t96 



appp:ndix. 



Fig. 65(i. 



Bfot assuniiiig tlieir strange forms. P>om the non-segmented, 

 sac-like larva it passes directl}^ into the pupa state. 



The development of Teleas is like that of Platygaster. 

 :Fig. 6n6 A, represents the egg ; B, C\ and i>, the first stage 



of the larva, the ab- 



s c domen (or posterior 



division of the body) 



'j\ " being furnished with 



|te./. „j a series of bristles 



''"^ ^V on each side. B 



g)/vi|:Y(« *"" represents the ven- 



^^/ ill b *^^^' ^ the dorsal, 

 and D the profile 

 view ; at, antennse ; 

 mcl, hook-like man- 

 ^ dibles ; mo, mouth ; 



6, bristles ; m, intes- 

 '' tine ; sw, the tail, 

 and id, under lip, or 

 labium. In the sec 

 ond larA'al stage, 



Devt'lopiiieiit of Egg-parasites. 



■which is oval in form, and non-segmented, the primitive band 

 is foriiKHl. 



Thk Embkyonal Membranes of Insects. — After the forma- 

 tion of the germinal layer or blastoderm, the outer lajer of 

 blastodermic cells jieels off or moults, forming the so-called "am- 

 nion" ("parietal membrane" of Brandt, Fig. 657, am). This 

 skin is a moult from the blastoderm. At a later period, after 

 the formation of the primitive band, a second membrane (Fig. 

 657, db "faltenblatt" of Weismann ; visceral layer of Brandt) 

 separates from the primitive band. It surrounds the embryo 

 in the Hymenoptera, Diptera and Coleoptera, enveloping the 

 limbs, and is shed as a thin pellicle when the embryo leaves 

 -the egg. Melnikow (Archiv fiir Naturgeschichte, 1869, p. 136) 

 from whose article the accompanying figure is taken, shows 

 that in the lice, however, 1)()th the amnion and visceral mem- 

 brane share in building up the body of the embryo, and pass 

 rfpon the dorsal side of the embryo. Brandt (Memoirs of the 



