HERPYLLOBIITS ARCTICUS. 
391 
it gave off two small processes. Along almost the whole 
length there were red dendritic markings, but no cell 
boundaries were visible : in spirit specimens some lacunae 
showed. 
This structure has been the source of some controversy; 
Sreenstrup and Liitken (12) first described it as part of the 
parasite, but Kroyer (7) some years later regarded the 
chitinous “ sucker” as the end of the parasite, and Schiodte 
(11 ) agreed with Kroyer that no integral part of the parasite 
was inside the worm. He recognised two terms used by 
different observers, “opsvulnet” and “ tungedannet,” 
Text-fig. 2. 
and explained their meaning by translating the first as a 
“tumour” formed by the worm, and the second as a 
“ tongue-shaped body ” hanging fiom the sucker and caused 
by some excretion from the parasite coagulated by spirit. 
Sars (10) also agreed with Kroyer, but as his specimen of H. 
c r assi r o st r i s was still attaclied to the host, the part in 
question would not show. Claus (1), describing H . arctic us, 
thought that the front part was pathological. 
Levinseu (9) then went thoroughly into the question, and 
found by making a cut through the stalk that the cuticle sur- 
rounding the root system appeared to be continuous with that 
of the stalk. He also made careful measurements of the two 
portions of fourteen individuals, and obtained the following 
