williston: apiocerid^. 109 



apiocera. mydaidae. 



Ocelli present. Ocelli wanting. 



Thorax with bristles. Thorax without bristles. 



Scutellum large, projecting be- Scutellura small, not projecting 



yond the metanotum. beyond the metanotura. 



Legs with numerous bristles. Legs with few or no bristles. 



Antennae with a short simple Antennae with a lamellate, 



style. jointed style. 



Discal cell short. Discal cell more elongate. 



Male forceps enlarged. Male forceps small. 



In all these respects Apiocera agrees with the Asilidae. I would 

 therefore propose the following as the definition of the Apioceridae: 



Rather large, elongate, chaetophorous flower-flies. Ocelli present. 

 Front not excavated; antennae with a simple short style. 

 Face short. Proboscis with pseudo-tracheate labella; the paraglossae 

 elongate; with one- or two-jointed palpi. Third longitudinal vein 

 of the wing furcate or not; one or both of the veins from the discal 

 cell terminatingbeyond the tip of the wing; five posterior cells. Em- 

 podia wanting. Male forceps enlarged. 



Apiocerinae. Palpi two-jointed, large; the second vein from the 

 discal cell terminates beyond the tip of the wing. 



Rhaphiomidainae. Palpi one-jointed, small; the second vein from 

 the discal cell terminates before the tip of the wing. 



MOUTH-PARTS. 



In the following pages, I give a rather brief description of the mouth- 

 parts in the Apioceridae and the allied families. It will be observed 

 that I make use of the terms proposed by Smith, as the result of his 

 comparative study of the mouth-organs. I believe that his studies 

 show a real advance in the knowledge of the homologies of these parts, 

 though in some instances his views may require modification or 

 change. The corresponding terms used by Smith and Dimmock, so 

 far as they affect our present purpose, are as follows: 



Smith. Dimmock. 



Paraglossae Labrum-epipharynx 



Ligula Hypopharynx 



Palpifer Maxilla 



Maxillary palpus Maxillary palpus 



Galea Labium 



Labellum t . Labellum 



