3 I 8 ENTOMOLOGY 



Origin -of Castes. Grass! maintains that all the forms are 

 alike at birth except as regards sex, and that the differences 

 between worker and soldier, which are independent of sex, 

 depend probably upon nutrition. Grassi attributes all the di- 

 versities of caste, except the sexual ones, to the character and 

 amount of the food. 



Food. The food of termites is of six kinds : ( i ) wood ; 

 (2) matter emitted from the oesophagus or rectum, termed 

 respectively stomodaeal and proctodseal food; (3) cast skins 

 and other exuvial *stuff ; (4) the bodies of their companions; 

 (5) saliva; (6) water. Of these the proctodaeal food is the 

 favorite. Nymphs receive at first only saliva; later they get 

 stomodaeal and proctodaeal food until, finally, they are able to 

 eat wood the staple food of a termite. 



American Species. Our common termite is Tertnes ftavi- 

 pes, which occurs throughout the United States, excavating 

 its galleries in decaying logs, stumps or other dead wood. The 

 nuptial flight of this species takes place in spring, when the two 

 sexes swarm in numbers that are sometimes enormous. One 

 swarm, as recorded by Hagen, appeared as a dense cloud, and 

 was being followed and attacked by no less than fifteen species 

 of birds, among which were robins, bluebirds and sparrows ; 

 some of the robins were so gorged to the mouth with termites 

 that their beaks stood open. Though plenty of winged fe- 

 males are said to occur in the swarming season, a true queen 

 of T. flavipes is as yet unknown, the queen described by Hub- 

 bard being evidently, from her undeveloped wings, a substitu- 

 tion queen. 



In the Western states, six species of termites are known, in- 

 cluding Termes lucifugus, which has probably been introduced 

 from Europe. In this species the primary queen is known to 

 exist. Regarding the Californian Termopsis angusticollis, 

 Dr. Heath says that if only one of the royal pair be destroyed 

 usually only one substitution form is developed, but when both 

 perish, from ten to 'forty substitutes appear, according to the 

 size of the colony; furthermore a remarkable fact these 



