164 PROCEEDINGS ENTOMOLOGICAL SOCIETY 



gnion) have not attained the shape or length of those of the mature 

 soldier, there being at !east one later molt to maturity. After 

 the first radical change the head is pigmentless (the only pig- 

 mentation is at the inner margin at the tips and base of the 

 mandibles and the tips of the maxillae) not elongate, rounded, 

 tapering towards the base, (broad at apex) mandibles shorter and 

 broadening at base; labrum elongate, sub-elliptical, (tapering at apex 

 and slightly at base), wider than in mature form; "menton" con- 

 vex, tapering, toward base, wider than in mature form. 



After the next molt, the nymph is as yet shorter than at matur- 

 ity, 4.5 to 5.5 mm. in length (flavipes) and the head is more elon- 

 gate but still broader at the apex; mandibles, labrum, and "men- 

 ton" more elongate and slender. Antennas with 14 to io segments. 

 At this stage the mouth parts and borders of the antennal sockets 

 are slightly pigmented. After another (?) molt, the mature size is 

 attained and pigmentation of the chitinized parts is taken on. 



Freshly molted, immature, pigmentless soldier nymphs of Tenn- 

 opsis angusticollis Walk, have just been observed among spec-' 

 imens collected by B. T. Harvey at Ashland, Oregon, August 28, 

 1913. 



It will be noted that there is a gradual elongation of the parts, as 

 the mandibles, labrum, and "menton," and that these parts become 

 more slender and lose in width. In this connection, it might be of 

 interest to state that in the neoteinic reproductive forms (nymph- 

 al forms with short wing pads developed from nymphs of the 

 second form) the head, thoracic and abdominal tergites and ster- 

 nites are both longer and broader than in the reproductive forms 

 that develop from nymphs of the first form, i.e., the structure at 

 this retarded early stage is more gross. 



In case of the nymphs of the sexed forms during the final molt, 

 i.e., from n,ymph to reproductive forms, the females of both nymphs 

 of the first and second forms normally 1 lose the genital appendices 

 which are present in both sexes prior to this molt but afterwards 

 only in winged males and neotinic male reproductive forms. How- 

 ever, egg-laying complementary queens, (with no indication of 

 wing-pads) of Termopsis angusticollis Walk, have been observed 

 with genital appendices; though they are absent in true queens 

 of this species. After this molt and quiescent stage nymphs of 

 the first form of Leucotermesspp. and Termopsis angusticollis Walk, 

 acquire wings and mature pigmentation and are colonizing sexed 

 adults ready for flight. Nymphs of the second form acquire a 

 characteristic pale pigmentation and develop to the neoteinic re- 

 productive forms. The whole period intervening between the 



1 Grass! and Sandias, Blandford's Trans, in Quart. Jour. Micros. Sri. vol. 

 39, ptt. 3, n. s. 1897. (Leucotermes lucij'ugus Rossi.) 



