134 THE INTEGUMENTAL SKELETON OF THE IMAGO. 



entirely removed from the part of the head to which the maxilla 

 is invariably attached in manducatory insects, it is impossible to 

 admit its homology with that organ. A seta might represent one 

 of the setas of the lacina, or of the galea, but not the maxilla itself. 



The following synonymy will be useful to those who desire to study the 

 maxillas of insects generally : 



Cardo, Kirby and Spence. Style, Audouin. Sous-Maxillaire, Bruile. 

 Stipes, Kirby and Spence, Burmeister. Maxilla, Newman. Maxillaire, 



Brulle". 

 Lacina, Macleay. Stipes, Erichson. Mando, Burmeister. Inter- 



maxillaire, Straus Durckheim and Brulle. 



Palpiger, Palpigere, Straus Durckheim, Burmeister and Audouin. 

 Galea, Fabricius. Upper lobe, Kirby and Spence. 

 Uncus, Kirby and Spence. Premaxillaire, Brulle. 



b. The Sclerites and Morphology of the Proboscis of the Blow-fly. 



The proboscis of the Blow-fly consists obviously of three 

 parts : a basal portion, the rostrum : an intermediate portion, 

 the haustellum ; and a terminal portion, the oral sucker. In 

 the use of the term ' rostrum ' I have followed Fabricius ; 

 ' haustellum ' is also one of his terms, but I have used it in a 

 different sense to that in which he employed it. Kraepelin 

 terms this portion of the organ, with the oral sucker, the true 

 proboscis, but no definite terms have hitherto been applied to 

 the several parts. 



The Rostrum or basal portion of the proboscis is a mem- 

 branous cone, attached by its base to the epistome, the genas, 

 and the pars basilaris of the head-capsule. It supports the 

 haustellum at its apex. 



The rostrum is somewhat flattened on its anterior surface, 

 and presents a horse-shoe-shaped sclerite, which forms a hinge 

 on the epistomum, being connected with its oral margin by 

 syndesmosis. I term this sclerite the clypeus. In using the 

 word 'clypeus' in this sense I have followed the nomenclature 

 usually adopted in the Diptera (see page 43). The clypeus 

 articulates with the labrum through the intervention of a tract 

 of syndesmotic integument, and as Fabricius applied the term 

 to the whole labrum, this use of it is not inappropriate. 



