I894-] 333 [Packard. 
Both Landois and Wagner figure the six rectal glands, which do 
not materially differ from those of other insects (Pig. IS, ^1, r.yJ). 
The Hypophartnx. 
Opinion regarding the homology of this unpaired piercing 
organ is by no means settled, and while there is a general agree- 
ment as to the nature of the paired mouth-parts, recent observers 
differ very much as to the morphology of the organ in question. 
It is the langue or lingua^ of Savigny (1816), the ligula of 
Kirby and Spence (1828) , the langue ou langtiette (lancette mediane 
du stcgoir) of Dug^s (1832), the lingua of Westwood (Class, ins., 
2, p. 489, 1840), "the unpaired median piercing organ" ("the 
analogon of the epipharynx of Diptera") of Karsten (1864), the 
"tongue" of Taschenberg (1880). 
Landois (1866) calls it the "stechorgan," not giving it a scien- 
tific Latin name in the text of his description, but adding the 
word lahrum in the explanation of the plates. He correctly figures 
and describes it, stating that it lies between the mandibles, and 
within the head expands into a flast-shaped portion provided 
Avith a chitinous edge on each side. Behind this point the chitinous 
edges diverge from each other like a ^?av of legs, forming the 
support for retractor muscles. Directly behind the enlarged 
flask-shaped portion between the chitinous legs begins the pharynx 
which dilates directly behind its origin, then contracts and passes 
into the oesophagus. The anterior portion of the pharynx forms 
a membranous tube provided with muscles, into which the bladder- 
shaped and other salivary glands open (Fig. 19). 
By this description of Landois it will thus be clearly seen that 
this organ has nothing to do with a labrum or epipharynx, but 
belonging to the floor of the mouth, in close relation to the labium, 
and receiving the salivary duct, must be a true hypopharynx. 
Like Karsten, he detected the ending of the salivary duct at 
this point. 
We copy Landois's figure of the hyj)opharynx as a whole 
(Fig. 19), and add a sketch of the hard parts observed in the flea 
of the Eui-opean hedgehog (Fig. 23). 
' Landois erroneously writes "ligula," p. 18. Tliis author also misrepresents Duges 
("labrum, Dugcs") who emphatically states that the labrum does not exist in Pulex 
{et II y fit cliez le lauii iin labre (pd n'exide pas chez la puce), p. 151. 
