28 PROCEEDINGS OF THE ACADEMY OF [1881. 



lata, as determined by Dr. Engelmann, ■who sent me the same gall 

 in 18*74, though I had previonsl}' collected it myself. It is, un- 

 doubtedl}-, an undescribed gall, and a A^ery similar one occurs on 

 the Quercus macrocarpa in the Mississippi vallej'. It has the 

 ordinary woody texture that belongs to so many Cynipidous oak- 

 stem galls, and the architect develops in a paler cell that occupies 

 a large part of the interior of the gall. When fresh, the gall is 

 quite bright-colored, inclining to crimson or scarlet. It seldom 

 attains a larger size than an ordinary pea, and differs from similar 

 galls in my cabinet by having frequently a rather broad, flattened 

 crown, though this character is b}' no means constant.^ 



NocTUENAL Habits. — It has already been said that the ants 

 collect the oak-gall nectar by night. Observations daily re- 

 peated upon a number of nests, determined that they leave their 

 nests for the oak thickets at or near V.30 o'clock P. M., and 

 between that hour and 8 o'clock, which is about the time of sun- 

 set in July and August. PreAious to the departure, the crater, 

 gate and exterior of the mound become graduall}^ covered with 

 swarms of insects whose yellow bodies quite hide the red gravel 

 surface of the nest. The marching of the honey-gatherers has 

 already been described, but always there remained a very numer- 

 ous force at home, who were seen at all hours of the night on 

 guard within and around the gate. (PI. V, fig. 25.) The return 

 home began about or a little before midnight, and continued until 

 between four and five, which was near da^'light at that season. 

 One or two extracts from my field notes will indicate the facts on 

 this point. " 11.30 P. M. Some ants returning home ; the move- 

 ment ver}' slow and deliberate. . . . 12.30. Quite a number 

 are now returning. Some are also still going outward. Numbers 

 of workers patrol the moimd and vicinity challenging nearl}' all in- 

 comers, who have to stand the test and give the required satisfac- 

 tion. What is the antennal password ? None of the returning 

 repletes are tolled bj^ the home sentries. . . . This morning 

 at 4,10 A. M. the ants were seen coming in from the oak bushes, 

 most of them well laden, but others not so full. There are 

 evidentl}^ degrees of success in honey-gathering among them. 

 Some of the dwarfs had very full abdomens. . . . 4.30 A. M. 



^ He suggests for the gall the name Cynips quercuB-mellarm. Am, 

 Ento, Dec. 1880. 



