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TEXT-BOOK OF ENTOMOLOGY 



eye-buds is situated a nervous expansion which is connected by a 

 nerve with the supraoesophageal ganglion. This nerve becomes the 

 optic nerve of the perfect animal, while the optic ganglion is clearly 

 separated from the brain. 



In the anterior, more cylindrical or tube-like part of the brain- 

 appendage we find the " frontal buds " (ss), on which the antennal 

 rudiments (at) soon bud out, in exactly the same way as the rudi- 

 ments of the limbs arise from the imaginal buds. 



Originally (Fig. 628, A) the brain-appendages lie tolerably far 

 behind in the thorax of the larva, so that they connect the hinder- 



Fit;. 6-!*. Diagrammatic representation of the position of the imaginal buds in the larva (A) 

 and pupa (/>') of Musca (the winj* rudiments omitted): u#, eye-buds ; <//, antennal perms: b l -1> 3 , 

 perms nl' the leps ; h<t, central gang-Home cord : g, brain ; h, so-called frontal appendage (Ifinntii- 

 huii(i)'. in. pt'riptitlal membrane; o, opening of the frontal appendage into the pharynx; oe. 

 resopliiigns ; j>. Mi-called " pharynx " ; r, rudiment, of the proboscis ; sx, frontal bud ; */, .stalk-like 

 connection of the pcripodal membrane with the tiypodemiis ; /-///, 1st, 2d, and od thoracic seg- 

 ments. Adapted from Van Kees, by Korschelt and Heider. 



most part of the wall of the pharynx Avith the foremost section of 

 the brain, Avhich they surround in the form of a mushroom. After- 

 wards, hoAvever, subsequent to pupation, they move, together Avith 

 the central nervous system, farther fonvard (B), whereby they (if 

 AVC have correctly understood the descriptions of Weismann and 

 Van Kees) laterally surround the pharynx Avith their anterior 

 end, Avhich is somewhat ventrally bent. At the same time, there 

 becomes established a gradually widening communication (B, o) 

 between the bni.in-appenda.gr and thr pharynx, Avhich soon extends 

 in the form of a lateral pharyngeal fissure along the entire length 

 of the brain-appendage. As a result, the cavity of the brain- 



