ANATOMY AND PHYSIOLOGY 



37 



interpretation he was followed by others, including the writer, who 

 (Folsom, 'oo) termed them "superlinguae." The writer at present 

 agrees with Crampton, however, that these appendages are homologous 

 with the paragnaths of Crustacea. If they are not equivalent to the 

 first maxillae of Crustacea, the term "maxillulae" should not be applied 

 to them; they may be termed " superlinguae " or "paragnaths," as one 

 prefers. 



Following the superlinguae are the maxilla, or under jaws, which are 

 less powerful than the mandibles and more complex, consisting as they 

 do of several sclerites (Figs. 45, 48). Essen- 

 tially, the maxilla consists of three lobes, 

 namely, palpus, galea and lacinia, which are 

 borne by a stipes, and hinged to the skull by 

 means of a cardo. The palpus, always lateral 

 in position, is usually four- or five-segmented 

 and is tactile, olfactory or gustatory in function. 

 The lacinia is commonly provided with teeth or 

 spines. The maxillae supplement the mandi- 

 bles by holding the food when the latter open, 

 and help to comminute the food. Additional 

 maxillary sclerites, of minor importance, often 

 occur. 



The labium, or under lip, may properly be 

 likened to a united pair of maxillae, for both 

 are formed on the same three-lobed plan. 

 This correspondence is evident in the cock- 

 roach, among other generalized insects. Thus, in this insect (Fig. 45) : 



FIG. 47. Left superlingua 

 of Machilis variabilis. g, 

 galea; /, lacinia; p, palpus. 



LABIUM = MAXILLAE 



palpus = palpus 

 paraglossa = galea 



glossa = lacinia 

 palpiger = palpifer 

 mentum = stipites 

 submentum with gula = cardines 



In most mandibulate orders the glossae unite to form a single me- 

 dian organ, as in Harpalus (Fig. 49, g). The labium forms the floor of 

 the pharynx and assists in carrying food to the mandibles and maxillae. 



The tongue, or hypopharynx, is a median fleshy organ (Fig. 45) 

 which is usually united more or less with the base of the labium. In 



