NEW MALLOPHAGA. 467 



presently to be described. Just below this bone there is 

 a double elevated ridge covered with short hairs (plate 

 lxiv ?> fig. 11). 



"The lower lip (plate lxiv, fig. 10) is composed of an 

 oblong mentum (m) bearing a larger labium (lb) nar- 

 rowed at the base, then expanding so as to have a bisin- 

 uate, almost S-shaped lateral outline; the lower edge 

 bears two short, broad lobes, and two stumpy, one- 

 jointed * palpi (l.j>.). The labium in profile (plate lxiv, 

 fig. 9) is very thick, and the lower edge is divided into 

 two narrow laminae, while still a third lamina, well sepa- 

 rated from the first two, forms the tongue (plate lxiv r 

 fig. 9, /). Within the tongue lie a pair of peculiar organs 

 which may be called the lingual glands (plate lxiv, figs. 

 9 and 10, l.g.) ; these can be seen through the semitrans- 

 parent mentum and labium, as in plate lxiv, fig. 10, offer- 

 ing an irregular, obovate outline. A short duct from the 

 lower end of each gland leads into a common duct (l.d.) 

 which opens in the oesophageal bone as already de- 

 scribed. 



" The ducts curve over the lower end of the glands and 

 run up their posterior surface, to which they are soldered 

 nearly to the top. The line of the ducts, together with 

 the lateral outlines, give the glands a three-cornered shape, 

 somewhat like that of a butternut. A little triangular cap 

 fits on the summit of each gland, and on it is inserted a 

 suspensory muscle, the upper end of which is attached to 

 the cranium (plate lxiv, figs. 9 and 10, g\m.) . The spec- 

 imens at my command have not been fresh enough to 

 study the histology of these organs, but they seem to be 

 composed of an outer sack, with a thin tough wall which 



"*With Westwood I regard these pieces as true palpi, and not as a sec- 

 ond pair of labial lobes." 



