124 C. B. THOMPSON AND T. E. SNYDER. 



genera Termopsis Heer, Calotermes Hag., Neotermes Holmg., 

 and Cryptotermes Banks, but the activities of workers are carried 

 oh by the nymphs of the reproductive forms. 



There is no soldier caste in the genus Anoplotermes Fritz 

 Miiller; this caste is also lacking in the genus Eutermes Fritz 

 Miiller, but here a new sterile caste has appeared: the "nasutus," 

 a soldier-like form with a prolonged frontal process or "beak," 

 which is often erroneously termed a soldier. 



Many tropical species of termites have two types of soldiers 

 and workers occurring within the species. The differences, 

 however, are not marked structural ones but are quantitative, 

 consisting mainly in the relative sizes of the two types, there 

 being both "large" and "small" soldiers and "large" and "small" 

 workers. These two types of worker or soldier or both, are said 

 to occur in the genera Rhinotermes Hag., Acanthotermes Sjost., 

 Termes Linn., Hamitermes Silv., Cornitermes Wasm., Eutermes 

 Fritz Miiller, and Leucotermes Silv. In tropical species of Euter- 

 mes two types of nasuti, large and small, have been found. In 

 our Nearctic termites, only two species have been seen with such 

 differences in the soldiers. In two new species of Calotermes from 

 Florida there are slight differences in the shape of the heads of 

 soldiers from the same colony, and in Reticulitermes n. sp. from the 

 Pacific coast there are also differences in the length of the heads of 

 soldiers, but from different colonies (see Table II.). 



FIELD OBSERVATIONS AND ARTIFICIAL BREEDING EXPERIMENTS. 



With the collapse of the fantastic theories of Grassi and others 

 in regard to the voluntary manufacture by the workers of "sub- 

 stitute" and "complemental" royal forms to replace the loss 

 of the "true," winged, or first forms, we find ourselves at a loss 

 to furnish the answer to the question how the different repro- 

 ductive castes actually reproduce their kind today. Do the 

 winged adults of the first form today give rise to the adults of 

 the second and third forms as well as to the workers and soldiers? 

 or does each fertile caste reproduce only its own fertile type 

 together with the sterile forms? 



Field observations upon species of the genus Reticulitermes 

 by one author (T. E. S.) indicate that reproductive individuals 



