BRAIN OF THE 'WHITE ANT' 589 



formige Druse) besitzen, aus Formen ohne driisige Fontanellplatte 

 stammen miissen. Da es wenig wahrscheinlich ist, dass eine driisige 

 Fontanellgewebe unabhanig bei verschieden Termitengruppen ent- 

 standen ist, so miissen wir die jenigen mit Fontanelplatte und die 

 jenigen mit schlauchformiger Fontanelldrlise von einer gemeiasamen 

 Ausgangspunkt ableiten. 



7. It is always questionable whether comparisons should be 

 drawn between invertebrates and vertebrates, but it does not 

 seem wholly improbable that the frontal gland of the termites 

 may have had a phylogenetic history similar to that of the 

 vertebrate pineal gland. The disappearance of the simple me- 

 dian vertebrate eye may be understood in conjunction with the 

 increasing complexity of the compound ej'es, and a brief survey 

 of termite habits may throw light upon the causes of the dis- 

 appearance of this median invertebrate eye. The true sexual 

 adults are the most conservative and primitive in structure and 

 in habits of all the castes. They are deeply pigmented, possess 

 long functional wings, and for a short time lead an aerial exist- 

 ence like other tj^^ical winged insects, and unlike all the other 

 members of the conununity. After the short period in the air, 

 which termite observers tell us is not a nuptial flight, the true 

 adults abandon their normal ancestral mode of life and begin a 

 secondarily acquired existence within the total darkness of their 

 burrows. Here the long wings are shed, mating takes place, and 

 from henceforth they live ^^^thin the dark and narrow chambers 

 of the nest. It is possible that this sudden and marked change 

 of environment may account in part for the disappearance of the 

 median eye in the ancestral termite and that the frontal gland 

 may have arisen in response to some new need. 



SUMMARY OF RESULTS 



The purpose of this study is to compare the brains of the 

 different castes of L. flavipes, and, further, to compare them with 

 those of the castes of ants, since both termites and ants are 

 social insects with a highly organized conununity life, but with 

 a very different degree of specialization and intelligence. 



The forms whose brains are here discussed are: the nymph of 

 the first form, with long wing pads, the njnnph of the second 



