BY FREDERICK A. A. SKUSE. 29 



those of the flagellum. Beneath the antennee there are some- 

 times found loDgitudinal furrows [fovece antennales) for their 

 reception. The sides of the head, from the eyes downward, are 

 called cheeks {genoi). A somewhat swollen ring sometimes 

 surrounds or partly encompasses the compound eyes, and is termed 

 the orbit (orbita), the successive parts of which are called the 

 anterior (orbita anterior sive facialis), inferior (inferior s. genalis), 

 posterior (posterior s. occipitalis), superior {stijierior s. verticalis), 

 and frontal (frontalis) orbits. Where no such ring is visible, a 

 distinct colour or some peculiar sti-ucture marking the nearest 

 surz'oundings of the eyes is described as an orbit. We will now 

 pass on to the mouth (os). The oral parts employed for sucking 

 are called the sucker or proboscis (proboscis) ; when attached to 

 a long and generally cylindrical prolongation of the head, this 

 part is called the snout or rostrum (rostrum), and must be dis- 

 tinguished from the latter organ. They may project from a wide 

 aperture often occupying a great part of the under surface of the 

 head, called the mouth-hole (cavitas oris). The common fleshy 

 root of the oral parts is connected by a membrane with the 

 border of the mouth. This membrane often has a fold, sometimes 

 almost corneous, and is then called the clypeus or shield (clypeus s. 

 ]ii-(dabrura ) ; it is either entirely concealed by the anterior 

 border of the mouth and is then usually movable, or it projects 

 over it as a ridge and is then usually immovable. Generally the 

 largest of the moutli-parts is the fleshy under lip (labium or 

 hy2)Ostoma), made up of the stem (stipes) and the knob (ca]ntuhc7n 

 labii) formed by the two suctorial flaps (labella). Close by are to 

 be seen the palpi (palpi), which are important to notice, being 

 frequently very characteristic. The tongue (lingua), under jaws 

 (maxillm), upper jaws (mandibuhnj, and upper lij) (lahrvm), are 

 not only inconspicuous, Init generally diHicult to determine, and 

 rarely of value in distingui.shing species. 



According to Meinert (Ent. Tidskr. i. pp. 150-153) the mouth 

 consists of the p/utrynx, which is divided into two portions, the 

 epiphargnx and the hypnpharynx. This is followed by the first 



