CHAPTER V. 



THE INTEGUMENTAL SKELETON OF THE IMAGO- 



1. GENEEAL CHARACTERS OF THE EXO-SKELETON IN 

 INSECTS. 



Willis, as long ago as 1692, recognised certain analogies 

 between the cuticular skeleton of an insect and the osseous 

 skeleton of a vertebrate. Geoffroy St. Hilaire was the chief 

 exponent of the ideas which Willis enunciated, whilst Audouin 

 and his followers, amongst whom the great majority of the 

 present school must be included, persistently regard all such 

 views as misleading. No doubt, as far as details are con- 

 cerned, the followers of Audouin are right ; nevertheless, it 

 must be admitted that analogies exist, in the modern sense of 

 the word, whilst the most recent literature on the subject, the 

 writings of Patten and Gaskell, show that even in the wider 

 sense in which the word analogy was used by St. Hilaire, 

 there is more truth in his theory than has been admitted by 

 the disciples of Audouin. 



Bibliography.— The following works, with those quoted on page 7, deal 

 more especially with the external skeleton. 



36. Savigny, J. C, ' Mdmoires sur les Aniniaux sans Vertdbrds,' premier 

 part, 8vo, Paris, 1816. 



This work is the foundation of the present nomenclature applied to the 

 parts of the mouth in insects and arthropods generally. 



37. Latreille, p. a., ' Observations Nouvelles sur TOrganisation ex- 

 t^rieure et gdn^rale des Animaux Articul(fs, et h. Pieds Articul^s, et 

 application de ces connoissances h la nomenclature des principales 

 parties des memes Animaux.' M^m. du Museum d'Hist. Nat., torn. 

 viii., p. 169, 4to, Paris, 1822. 



38. AuDOurN, v., 'Recherchcs Anatomiques sur le thorax des .A.nimaux 



7 



