EXTERNAL ANATOMY OF INSECTS'. 375 



media] nervure ; or in Orthoptera, &c. between the 

 anal nervure and the posterior margin a . 



C Areolae (the Areolets). The smaller spaces into 

 which the wing is divided by the nervures. They 

 include the Areola? Basilares, Media?, and Apicales. 



a Areolae Basilares (the Basal Areolets). The pa- 

 rallel areolets of the base of the wing b . 



b Areolae Mediae (the Middle Areolets). The areolets 

 of the wing that lie between the basal areolets and 

 the apical c , 



c Areolae Apicales (the Apical Areolets). Those 

 areolets of the wing that terminate in or very near 

 the apex d . 



D Neurje (the Nervures). Corneous tubes, for expand- 

 ing the wing and keeping it tense, and to afford 

 protection to the air-vessels — commonly called the 

 Nerves. They include the Neura Costalis, Post- 

 costalis, Mediastina, Eocterno-media, Interno-media, 

 Analis, Axillaris, and Spuria. 



a Neura Costalis (the Costal Nervure). The first 

 principal nervure of the wing, close to or forming 

 the anterior margin in Lepidoptera, Hymenoptera^ 

 and Diptera; but sometimes remote from it in Teg- 

 mina e . It includes the Phialum and Hamus. 

 a, Phialum (the Phial). A little bag to receive fluid at 

 the will of the insect, by which the weight of the 

 wing is increased. It is found also in the under- 

 wings in Coleoptera f . 



a Plate X. Fig. % 3. d: '• Ibid. Fig. 7—15. e\ 



c Ibid./. <> Ibid, g: e Ibid. h\ 



f Chabrier Sur le Vol des Inseeies, Ann. du Mm. 3eme ann. i'23,. 

 4eme ann. 325 — . 3d Cahier 78. 



