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



termite soldiers occur despite the presence of soldiers with wing- 

 pads, nor is any data at hand as to their progeny, although Heath 

 (1903) has recorded fertile soldiers in the species Termopsis angus- 

 ticollis Hagen that produced "normal progeny." In fact, recent 

 histological work by Miss Thompson has definitely proved that 

 soldiers with wing-pads are not fertile. 



Attempts at Cross-Breeding. 



In colonies of Reticulitermes, in logs in the forest, sometimes 

 a male of the first form is found with numerous (as many as 

 sixteen) mature females of the second form. Grassi would have 

 described these second form females as "substitute" queens, pro- 

 duced by the workers to fill the place of a missing "true" first 

 form, dealated queen. 



It is an open question how they are to be accounted for with 

 our present knowledge, as we have no exact data as to the progeny. 



In another instance, three queens of the third form and one 

 queen of the second form of a species of Reticulitermes were 

 found together in the same colony. However, both sexes of two 

 different mature reproductive castes have never been found in one 

 and the same colony of a species of Reticulitermes. 



On account of the lack of reliable data on the progeny of such 

 reproductive forms which undoubtedly were cross-breeding under 

 natural conditions as previously stated, (Thompson and Snyder, 

 1919), it was planned to undertake, with Miss Thompson, a 

 thorough investigation of the termite castes, especially of the 

 three stable reproductive types, with an analysis of their breeding, 

 to be carried on by means of field and laboratory observations and 

 by breeding experiments which would require several years to 

 complete. A beginning was made in the spring of 1919 to cross 

 reproductive forms of different types of Reticulitermes flavipes 

 under artificial conditions. The following is a brief summary of 

 these attempts: 



Methods. 



A large series of young second form female adults of Reticuli- 

 termes ftavipes, which possibly may have been fertilized by second 

 form males, were taken from a fairly small colony and placed 

 with mature first form dealated males, which had not copulated, 

 in small shallow cells in decayed wood sunken in moist sand in glass 

 jars and tin boxes. 



Results. 



After a period of ten days to two weeks all these second form 

 females had died, but the first form males were still living and were 

 active; they evidently were prepared to forage for themselves, 



