THE MYCETOPHILID^. 95 



jointed ; in this the first joint is fleshy, and divided into two by a 

 horny ring ; second joint cyUndrical and horny ; third joint short, 

 often bearina; a bristle. 



Fic. 13. — Mouth parts of il/jw^/(/ larva. — n. Labrum ; f3. Maxilla; y. Mandible: 



I. Labium. 



Ocelli may be present, and are figm-ed by Osten-Sacken in his paper 

 as a small, pellucid conve.x spot below the antenna; in Mycetophila 

 larvag. 



The mouth parts of the larvie are typical and normal, consisting 

 of labrum, mandibles, maxillw, and upper lip. 



The labrmn. Fig. 13 (a), is fleshy and encased in a horny frame ; 

 its function, according to Osten-Sacken, "seems to be, principally, 

 to shut the oral orifice, and perhaps to press on the mandibles and 

 ma.\ilku during the process of mastication." 



The maxilliC, Fig. 13 (5), are horny and serrated on the inside. 



The maxillce consist of two ])ieces : a triangular cardinal piece {,/) 

 and a sfirps composed of two distinct pieces, an inner and outer {b) 

 and {a); the inner one has a serrated lobe on the inside, showinc^ 

 much analogy of structure in all the larvae {Sciara has six or seven 

 indentations, MycetopJiita ten or eleven). A rudimentary palpus is 

 present in some forms (6'a('/'/«'Aj') ; it is 2-jointed. In other genera 

 it is very rudimentary. 



The upper lip, Fig. 13 (o), little developed. Usually as a V-shapcd, 

 horny piece between the maxilla?. This may have some function in 

 connection with the cocoon spinning of the larvse. 



The Ma?idibles, Fig. 13 (7), are horny lamels serrated on the 

 inside, and are compressed between labrum and maxilla;. 



The general form of the body is sub-cylindrical, elongated, and 

 fleshy, white or yellowish, and composed of twelve segments. la 

 many it is serpentiform {Sciophila), some stout {BolitopJiila). Tiie 

 skin is smooth ; hairs on the ventral surface. Eight pairs of stigmata 

 are present : one pair on the first thoracic and seven on the first 

 seven abdominal segments. The larva; are generally transparent. 



