26 PROCEEDINGS OF THE ACADEMY OF [1881. 



cases became beaded with six or more globules, several times 

 larger than a pin-head. By removing these beads successively, I 

 found that during the night one gall gave out at least three series. 

 The continual flitting of the ants from branch to branch and gall 

 to gall, was thus explained : the successive exudations invited 

 their frequent return to the galls from which they had formerly 

 fed. When the branch had first been brought to the tent, some 

 of the gall-bearing twigs had been clipped off and placed within 

 the artificial nests, but received no attention from the ants. Some 

 of the bleeding galls were now introduced, which were instantly 

 covered by the ants, and soon cleaned of their beaded sweets. 

 An examination of the first galls explained the reason for their 

 neglect — they were sapless. 



Nectar-producing Galls. — A number of galls of various sorts 

 and sizes, was collected for dissection. They were readily divided 

 into two classes (1), the livid and greenish galls which were soft 

 and entire ; (2) the darker colored ones which were hard, unjneld- 

 ing to the touch, and pierced at one side by a small, smooth, reg- 

 ular, cylindrical cavity. It soon appeared that the bleeding of 

 honey -sap was confined to the first class. Upon cutting away the 

 soft pulpy fruit (if it may be so termed), a hard whitish-green 

 ovoid cell, not unlike a cherry seed, was found at the centre. It 

 was about one-eighth inch in diameter. Lying outside of and 

 against this, in a little cavity, I found in one gall a minute, living- 

 grub (PI. Ill, fig. 12). The body was white, of eleven segments, 

 the head tipped with a brownish hue. The inner cell when opened, 

 showed a spherical cavity in which was a very minute gelatinous 

 pyriform object, which adhered to the side of the cavity. I had 

 no microscope with me, and in lieu of facts, can only conjecture 

 that this may have been an embryonic form of an insect, which 

 matures later in the season. * 



The hard galls were next dissected. They are all pierced on 

 one side, invariably near the base (figs. 10, 11), by a circular open- 

 ing made by the matured gall-insect in its escape. Fig. 11 repre- 

 sents one of these, a turban-shaped gall, magnified about three 

 times the natural size. A section view of the gall (fig. 10) shows 

 that the exit hole (eh) penetrates the interior cell-ease, which 

 must therefore serve as the cocoon in which the pupa transforms. 

 Inside of some of these cells I found traces of a flossy texture. 

 The cells are commonly spherical, but (as in fig. 10) sometimes 



