52 KELLOGG: SCLERITES OF THE HEAD. 



observations lead me to contradict statements in Mr. ICdward Burgess's 

 *memoir on the anatomy of archippus. 



This suture in the head of archippus is shown as sii in fig. ii, Plate 

 II. This suture was apparent in all of the few lepidopterous heads 

 examined by me, except in specimens belonging to the genus Hepialus. 

 It is shown as it appears in Protoparce Carolina at sii in fig. 2, Plate 

 II; in Argynnis cybele at su in fig. 5, Plate II; in an exotic Hesperid 

 butterfly at su in fig. 4, Plate II; in Hemaris thysbc at su in fig. 12, 

 Plate II. It extends uniformly from fossa to fossa. In Actias luna 

 it is very short, as the clypeal tongue tapers almost to a point, meet- 

 ing the similar narrowly pointed, forward-projecting tongue of the 

 epicranium. The clypeus in archippus is shield-shaped. The sutures 

 between it and the gena^ are fairly distinct, and each one is accom- 

 panied in its upper half by a ridge. The lower half of each suture 

 (that part separating the triangular expansion of the gena from the 

 clypeus) is especially distinct, and in bleached specimens ai)pears as a 

 linear space with a noticeable expansion near its point of intersection 

 with the sutural ridge above mentioned. This also is the case in the 

 heads of certain other lepidoptera (see in Argynnis fig. 5, Plate II, 

 and in nn exotic Hesperid, fig. 4, Plate II). In Protoparce Carolina 

 only the lower portion of each suture is distinct, though a well defined 

 ridge separates the two sclerites above. In Triptogon uiodcsta the 

 clypeus apparently extends cpiite to the eye on each side. 



Genae 



PetwcLii Inc t iypcus and liic eyes arc the narrow, elongate gciue. 

 They compose the front portion and part of the u])per and lower 

 portions of the orbits of the eyes (see gc in fig. 11, Plate II). Fach 

 gena presents a triangular expanded portion lying between the base of 

 the maxillar proboscis and the lower inner angle of the eye. Triptogon 

 modesta seems to have no elongate portion extending upward from the 

 triangular ex])ansion, tlie clypeus apparently extending laterally to the 

 eyes. The gena in archippus bounds the antennary fossa outwardly, 

 and extends up and back to the post-gena. In archippus the suture 

 between gena and post-gena is obsolete (see fig. 9, Plate II), but it is 

 distinct in most Lepidoptera (see su^ in fig. i, Plate II, Protoparce 

 Carolina; s//^ in fig. 3, Plate II, Pamphila leonardus; su^ in fig. 6, 

 Plate II, Actias luna). The suture between the epicranium and that 

 part of the gena lying behind the antennary fossa is obsolete in 

 archippus (see fig. 9, Plate II). This suture is usually present in 

 the lepidopterous head (see jv/" in fig. i, Plate II, Protoparce caro- 



*Burgess. Ed^^•.. Contributions to the Anatomy of the Milk-weed Butterfly. Danais 

 arc>ii/jijiis Yah. lt<K(j. IJoston. Mr. Uurfress .says: •'■ The face iut-ludes the regiou below the 

 anteunaj. au(i is formed ehietly tiy the larfje vaulted clypeus. whose arc-shaped lateral 

 boundaries are well marked, while above it passes directly into the epicranium without 

 any suture or line of demarcation as found in many insects." 



