PHYLOGENETIC ORIGIN OF TERMITE CASTES. 123 



C. minor Hagen, and other species of Calotermes. Vestigial wing 

 pads are evidently of frequent occurrence in this genus although 

 these soldiers are in general not fertile. 



The Rev. F. L. Odenbach, S.J., of Cleveland, Ohio, has kindly 

 loaned his manuscript notes from which we quote. In one of 

 Odenbach 's colonies of Reticulitermes flavipes, an enlarged egg- 

 laying queen, figured in manuscript notes and referred to by 

 Snyder (1915, p. 56), has the abdomen distended and the ab- 

 dominal tergites separated, but possesses long, well developed 

 wing pads like a nymph of the first form. 



Grassi (1893) has figured a queen which, in respect to the length 

 of the wing pads, is an intermediate between the first and second 

 forms in the species R. lucifugus Rossi. 



Another peculiar form has been found in a colony of Reticuli- 

 termes n.sp. from Montana. This specimen (a male) has the 

 .head heavily chitinized and yellow in color as in the soldier; the 

 mandibles and labrum are like those of the worker; but the head 

 is slightly more elongate than the typical worker head. The 

 total length of the specimen is nearer to that of the soldier. 

 Unfortunately the antennae are broken, so that the question 

 whether it is a worker or soldier can not be determined from the 

 number of segments. After staining, the frontal gland, the 

 compound eyes, the brain, and the sex organs were identified as 

 those of the worker caste (see Table I.). This specimen is evi- 

 dently only a worker of abnormal development, and not, as was 

 first thought, an intermediate form between the worker and the 

 soldier. 



An argument against the view that the termite castes are 

 mutations is the fact that the five castes are constant in their 

 structural characters and more or less constant in their occur- 

 rence throughout the very different and widely distributed 

 genera of the three families of termites. In the native American 

 genera listed in Table II. the first form or reproductive adult with 

 long wings is found in every genus. Either a second or a third 

 form adult is probably of similar occurrence. Sometimes both are 

 present, sometimes one or the other is said to be lacking. This 

 may be a real absence of the caste in question, or it may be due to 

 incomplete field data. There is no worker caste in the primitive 



