18 Annals Entomological Society of America  [Vol. VII, 
The larva of Decatoma flava also possesses four tubules. 
Two are long, clavate, and drawn to a point at their cephalic 
ends, and two are short with blunt ends, (Fig. 64, Pl. IX). 
They are more slender, the cells smaller, and the nuclei more 
regular than those of the Eurytoma larva. The general con- 
dition stated regarding the former also applies to Decatoma 
flava. 
It is interesting to note that the galls that contain the high- 
est percentage of parasites and inquilines, and those in which 
the larva of Dryophanta erinacei have been destroyed at an 
early stage never reach full development; also that the tissues 
become dry, hard, and brittle. It is largely from this type of 
gall that the summer brood of the inquilines, and of Eurytoma 
studiosa, and Eurytoma auriceps emerge. 
The Malpighian Vessels of other Gall-Forming Cynipide. 
In the agamic form of Holcaspis globulus (Fitch) the 
Malpighian vessels, as obtained from fresh material, are white 
in color. They consist of two long tubules with large, globose 
cells, and irregularly branched nuclei. They give evidence of 
a high state of activity, and on contact with a foreign sub- 
stance pour forth a fluid as did Dryophanta erinacei. In the 
degeneration of the larval tubules and the development of those 
of the adult they are similar to Dryophanta erinacei, (Figs. 54, 
Pi Vil-and’ 57, and 538,7PL Vaile 
The agamic form of Dryophanta polita (Bass.), which 
causes the polished oak gall, possesses two Malpighian vessels 
which as dissected out are white in color. They are smaller 
than those of Dryophanta erinacei and Holcaspis globulus. 
The cells are globose, nuclei irregular, and branched. Their 
general action is similar to those already discussed. In a 
longitudinal section they appear as in Figs. 55 and 56, Pl. VII. 
The process of degeneration of the larval tubules, and the 
development of the adult vessels correspond to that already 
described for Dryophanta erinacei. Fig. 55, Pl. VII, is a longi- 
tudinal section through a pupa of Dryophanta polita, which 
shows the degeneration of the larval tubules and the adult 
vessels forming. 
