546 The American Naturalist. [June, 
THE MOUTH-PARTS OF THE LEPIDOPTERA. 
By Vernon L. KELLOGG. 
By the association of the genera Hepialus and Micropteryx 
as a group of forms sub-ordinally distinguished from all other 
lepidopterous forms, and characterized by a distinctly general- 
ized condition of certain organs of the body, a special interest 
attaches to the study of the morphology of these genera. If 
the Jugate, as a sub-order of the Lepidoptera, is a more 
generalized group than the Frenate the morphology of its 
members is to be particularly studied for suggestions regard- 
ing the primitive form of the various organs of the lepidopter- 
ous insect, and, by summation, of the racial or ancestral type- 
form of the order. 
The commonly unqualified statement of zoological and ento- 
mological text-books that the mouth-parts of the Lepidoptera 
are of a type adapted for sucking, and that mandibles are 
wanting, or rudimentary, should not be longer repeated with- 
out qualification. It has been known since the publication of 
Dr. Walter’s study of the mouth-parts of Micropteryx that the 
genus presents conditions of mouth-parts obviously contra- 
dicting the common assertion, and undoubtedly the most 
generalized known among the Lepidoptera. The presence of 
functional, denticulate mandibles, combined with the absence 
of a maxillar proboscis, make the general] statement that the 
Lepidoptera are characterized by the possession of sucking 
-mouth-parts an untrue one unless suitably qualified. And 
although this qualification will depend upon the presence of 
functional mandibles in but a few species of moths belonging 
to a single genus, the noting of these few exceptional instances 
is, obviously, of extreme importance. Dr. Walter found func- 
tional, denticulate mandibles in Micropteryx aruncella and M. 
_ anderschella. Associated with the presence of the functional 
1 Walter, A., in the Jenaisch. Zeitsch. f. Naturwiss., v. 18 (1885), pp. 751-807, 
2 plates. 
