1914] A Study of Dryophanta Erinacet. an 
A series of the Malpighian vessels dissected out show this process 
(Pigs, 45, 49, 52, and 53, Pls. VI, and VII). 
The method of degeneration and the relation of the pha- 
gocytes to this process has been in question. In the process of 
degeneration as shown in Dryophanta erinacei, Holcaspis 
globulus, Dryophanta polita, and in the Eurytoma larva, it is 
clear that the phagocytes play no part whatever. The cells 
break down and pass into the alimentary tract. Fig. 50, PI. 
VII is from a cross section of a larva of Dryophanta erinacei, 
and shows a fragment of a cell of a tubule found in the lumen of 
the intestine. Fig. 51, Pl. VII is from a longitudinal section of 
a similar larva, and shows the degenerating cell just breaking 
away into the lumen of the intestine. Figs. 54, and: 57, Pls. 
VII, and VIII show the degenerating cells of Holocraspis 
globulus, also the adult vessels forming. Fig. 55, Pl. VII rep- 
resents the same condition in Dryophanta polita. 
The only instance where phagocytosis was found was in the 
larva of Trypeta solidaginis. Here as shown in Fig. 76, Pl. X, 
the phagocytes are present, but from a study of the slide it was 
evident that chromatolysis had already set in, and the phago- 
cytes were only of secondary importance in the degeneration 
of the cell, 
B. The Relation of the Oenocytes to Gall Formation. 
We must now consider the relation of the oenocytes to the 
production of the gall. Rdossig says ‘‘The oenocytes have a 
certain influence, in that they in some manner break up the 
blood fluid, and work it over in advance for the Malpighian 
vessels.’’ This conclusion rests on the following: First, a 
mere comparison of the size of the oenocytes with that of the 
larva; second, ‘‘The general opinion that they are excretory 
organs destined to store up urates, especially, as Verson has 
shown in Bombyx, during the time when the Malpighian ves- 
sells do not carry out their function, during molting and pupa- 
tion. Berlese is of the same opinion.’’ Lastly, a possible 
correlation in the development between the Malpighian ves- 
sels and the oenocytes. 
Rossig points out that the oenocytes of the various larva 
which he has studied reach an unusual size. This growth is 
attained within a short time, after which they shrink and 
