782 JOURNAL, BOMBAY NATURAL HIST. SOCIETY, Vol. XXI. 



The diameter of this nest is 2-85 m.; the height of the semi- 

 globular structure, without turrets, averages 56 cm. ; highest turret 

 measured from roof of substructure, 55 cm.; total height of nest 

 which was situated on a slightly inclined plane, 85 cm. on more 

 elevated side of slope, 110 cm. on lower. Mantle of nest not 

 perforated. 



From this normal type the nests " of Odont. oh. c differ consider- 

 ably ; for the pointed turrets are in this case replaced by small 

 roundish cupola-like prominences, the mantle of which is wholly 

 perforated. Moreover the fungus beds within the nest show quite 

 a different formation. If we add to this that the soldiers are a 

 little larger than those of the a-nests, with shorter labrum and 

 more strongly developed salivary glands, we should, it would 

 seem, be quite justified in considering the occupants of the a-and 

 c-nests as two distinct species. 



However, this view is contradicted by Odoniotermes obesus h, the 

 soldiers of which occupy an intermediate position between a and c^ 

 since in ^-colonies a-and c-soldiers are found promiscuously. The 

 structure of nest is likewise peculiar in group h ; its distinc- 

 tive features are the numerous small prominences or cupolas- 

 (cp. with the many turrets of obesus a) of low elevation (a& 

 in c) and completely separated (as in c) ; perforation is absent 

 ('as in a). 



The fourth c-nest (examined 10-6-1911 ; cp. above) is also 

 opposed to the abovementioned view ; for it shows the same 

 build as the 5-nest. Its occupants, however, belong to 0, 



obesus c. 



The conclusion, therefore, is that the three forms of obesus are 

 not entirely distinct biological types ; but, as far as I am at present 

 able to judge, the forms merge into one another with regard to 

 their morphological character as well as the striicture of their 

 nest. 



It is certain, according to Assmuth's information, that 0. obesus 

 belongs to those species of Odoniotermes which (like 0. ceiilonicus 

 and 0. Horni) use secretions of their salivary glands as means of 

 defence. 



