116 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 
chitinous stalks, all of which distinctly are as in Collembola, Campodea, 
and Japyx, except that the superlingue of Hemimerus appear to be 
fused with the lingua. Figure 10 of Hansen bears a close resemblance 
to my Figure 27 of Auurida, although Hansen says (p. 87), “ especially 
the structure of the mouth removes it [Hemimerus] very far [?] from 
the Thysanura and leads it to the Orthoptera.” 
In the young larva of Ephemera, Heymons (’96, p. 22, Taf. II. 
Figur 29) finds that “Der Hypopharynx entsteht . . . auf ahnliche 
Weise wie bei den Orthopteren. Auch an ihm findet eine Art Gliede- 
rung statt, dergestalt, dass von der eigentlichen Hauptmasse zwei laterale 
vordere Zapfen abgetrennt werden, die mit kleinen Harchen bedeckt 
sind, wihrend der eigentliche Hypopharynx am Ende einen Besatz von 
feinen (Sinnes-) Borsten tragt.” His figure of lingua and superlingue 
might fairly represent those structures of Anurida in Stage 7 (Plate 4, 
Figure 27). Inthe imago the mouth-parts are, of course, atrophied. 
In another Ephemerid nymph, Heptagenia, Vayssiére (’82, pp. 113- 
114, Planche 5, Figure 46) found a highly developed lingua, or hypo- 
pharynx, fused with large lateral pieces [superlingue ] and suggests that 
they indicate a distinct primitive segment, —a possibility which will be 
discussed later. He states (p. 106), ‘‘ La langue ou hypopharynx.. . 
est assez dévelopé chez tous les individus de la famille des Ephémérines, 
a exception du Prosopistoma, ot il est tres rudimentaire.” 
I shall not cite descriptions of the “hypopharynx”’ of additional in- 
sects, because I have nothing more to add, and the subject has been 
well treated of by Kolbe (90, pp. 213-217, Figuren 126-134), Packard 
(98, pp. 70-83, Figures 70-87), and others. Packard’s comparative 
account, in particular, is most excellent and well illustrated. (In his 
Figure 69, by the way, the abbreviations p. and hyp. should be inter- 
changed.) Briefly, the lingua is found in every order of insects, and 
although highly specialized in suctorial orders, retains, nevertheless, the 
same position and nearly the same relations to the salivary ducts that 
it does in the more generalized mandibulate orders which I have de- 
scribed. It is an interesting fact that in the Lepidopterous genus, 
Micropteryx, Walter (’85, Taf. XXIV. Figur 11) shows two hypo- 
pharyngeal stalks, readily comparable with those of Apterygota. 
The superlingue — which, as I have shown, originate quite indepen- 
dently of the lingua in Apterygota, but become more or less united with 
it in Orthoptera and Ephemerida — should hereafter be recognized as — 
morphologically important structures, and be searched for in even the 
most specialized haustellate orders as more or less intimate constituents 
