BRAIX OF THE 'WHITE A XT 557 



and that the latter have undeveloped sex organs. Que disad- 

 vantage of excluding these forms is that we are then left with 

 no general term to denote the full grown stage, which after 

 all is the original sense of the word adult. 



The adult stages may be divided into two grou])s: (1) forms 

 with functional and mature sex organs, the 'kings' and 'queens,' 

 of which there are three different types, (a) kings and queens with 

 long functional wings, the 'true' royal pair, (b) kings and queens 

 with short wing pads, the neoteinic substitute pair with short 

 wing pads; (c) kings and (jueens with no wing pads, the neoteinic 

 substitute wingless pair, sometinuv^ known as ergatoid or worker- 

 like; (2) forms with imdeveloped sex organs, (d) the 'workers,' 

 (e) the 'soldiei^.' making in all five adult castes. To these five 

 types of adults, tliicc inoic. lepresenting phases of a later devel- 

 opment, may be added, namely: the enormously distended fer- 

 tilized egg-laying (|ueens of the three (lueen types (table 1). 



The young, or the (ieveloi)mental stages of the five adult 

 castes, occur in many stages, the number of these differing with 

 the caste. From tlic egg hatch forms which are said to be all 

 alike and undiffeicntiated, (Irassi. Snydei', and from these undif- 

 fei'entiated nyin))li-. laiAae'of Snyder. 'develop nym])hs with large 

 heads and nymphs with small heads. The large-headed nymphs 

 develop "after a seiies of molts and (|niescent stages of com- 

 paratively short duration,'" the wiiole j^rocess requiring less than 

 one year, Snyder ('!()), into the sterile workers and soldiers. 

 The small-h(vided nym])hs undergo a more com])lex development, 

 which "api)arently recjuires two seasons," and develop into: (1) 

 nymphs of the 'first foiin.' witli long wing pads, which become 

 the true royal pair, the sexual adults with long wings, (2) nj'mphs 

 of the 'second form,' with short wing pads, which become the 

 sul)stitute sexual forms with short wing ])ads, (3) nymphs with- 

 out wing pads, whose devek)pment is not fully understood, and 

 whicli become the substitute wingless sexual adults. 



' llu' term nymph i.s used in tlii-s pajjor to donote any cl('vclo|)nicntaI stage 

 of an insect with incomplete nietamorpliosis. whether the form po.ssesses wing 

 inula or not. Snyder, in accordance with the older authors, applies the term 

 'larva' to the younger nymphs which possess rudiments of wing pads that can 

 only be distinguished with magnification. He uses the term nymph to designate 

 forms with wing pads that can l)e distinguished with the naked ey<\ 



