174 OTTO VERNON DARBISHIRE. 



in places where it is being pierced, it seems to become vacuolated. It 

 appears to be corroded in some way by the attacking filament of the 

 parasite (Plate XVII., Fig. 3). 



Fig. 6. Actinococeus roseus (Lyngb. ) Kold. Rosenv. The 

 shaded portion represents the parasitic neniathecium ; the 

 lighter portion is the thallus of the host-plant, n. large 

 primary neniathecium ; n*. smaller secondary neniathe- 

 cium just forming. x 40 diam. 



A large number of filaments pass out of the tissue of the 

 spermophore within a certain limited space (Plate XVII., Fig. 4) 

 On the outside of the spermophore they form dark-reddish 

 bodies, the nemathecia of Actinococeus subcW.aneus (Fig. 6). They are 

 all joined together in a common gelatinous substance, in which they 

 branch ; the branches finally radiating outwards in a direction from 

 the centre of the whole parasitic tissue. 



A.t first as a rule these nemathecial bodies are formed only on one side 

 of the flattened spermophore. Often, however, we see filaments arising 

 from the intramatrical tissue of the parasite, which pass out on the 

 opposite side of the spermophore (Fig. 6). When a second neniathecium 

 is formed, it may be separate, if it is produced exactly opposite to the 

 first ; if it is produced close to the first nemathecium and next to it. the 

 two frequently coalesce. 



Ultimately, owing to the almost pseudo-parenchymatic development 

 of the intramatrical tissue of the parasite, it is no longer possible in 

 older specimens to distinguish between the filaments of the parasite 

 and the ordinary tissue of the cortex and medulla of the host. As 



