PROC. ENT. SOC. WASH., VOL. 22, NO. 6, JUNE, 1920 III 



the result of such a stimulus as body odor perceived by contact, 

 which, according to Beebe (1919), is probably the governing 

 factor in establishing routes of travel by army ants in the tropics. 



The winged termite is not the only colonizing reproductive 

 form. Although the most striking form and the one that has in 

 the past received the most attention from entomologists, there 

 are other less conspicuous reproductive forms which are also im- 

 portant to the termite colony. The two most common of these 

 other reproductive types will be described in some detail and men- 

 tion will also be made of "intermediate" forms. 



The following pages will discuss the occurrences of these differ- 

 ent colonizing reproductive forms in colonies, their origin, devel- 

 opment, and the manner in which each type establishes new col- 

 onies regarding which, except in case of the winged adult, but 

 little is known. The progeny of the different reproductive forms 

 will also be described. A brief account of attempts at cross breed- 

 ing between two different types of reproductive forms will be 

 given. 



The Three Types of Reproductive Forms. 



In addition to the normal, pigmented, winged reproductive 

 forms that engage in this colonizing flight, there are two other 

 stable reproductive types. The more or less darkly pigmented 

 body, functional eyes, and aerial habit in colonizing (i. e., swarm- 

 ing) are found only in adults of the first form; after fertilization 

 they attain the greatest post-adult size. In general, there is a 

 subterranean mode of life, less body pigment, and smaller eyes 

 in the second and third form, the former caste having short wing- 

 pads, the latter being entirely apterous and worker-like. 



A brief descriptive comparison of the three different reproductive 

 forms will be necessary before the manner in which new colonies 

 are established can be described. 



Description of the Adults of the First Form of Species of Reticnlitermes 



Holmgren. 



The winged, sexual adults of the first form are deeply pigmented, 

 the compound eyes are pigmented and functional; this caste is 

 especially adapted for flight and is capable of enduring full sun- 

 light. Lightness of body for the colonizing flight is a primary 

 necessity and the admirable manner in which this has been at- 

 tained may be seen upon comparison with the other reproductive 

 forms particularly in the more slender thorax, mouthparts and 

 legs. 



"Stylets" or abdominal appendices on the ventral surface of 



