Fapers from Dr. Th. Mortensen’s Pacific Expedition 
1914 - 16 . 
XXVIL 
Planarians. Part IV. 
New Stylochids. 
By 
Dr. Sixten Bock, Uppsala. 
(With Plates III and IV). 
Introduction. 
The present paper deals with all the Stylochids collected by 
Dr. Th. Mortensen in the Pacific and in the Malayan Archipelago 
except the new genus Discostylochus already treated in a separate 
report. It is of special interest that the material has afforded an 
opportunity to increase the knowledge of the remarkable genus 
Enterogonia Haswell. The systematic position of this genus has 
been wrongly interpreted on account of the circumstance that certain 
for the classification highly important features have hitherto remained 
unobserved. It was supposed to lack tentacular groups of eyes, 
tentacles, and prostatic vesicle. As these features are not outstand- 
ing and must be especially searched for to be detected, it was 
rather permissible for the describer of it to fail to recognize them. 
Three new genera are represented in this collection. 1) Ilyplana 
from New Zealand is provided with a rich amount of cyanophile 
giands emptying their secretion in the antrum masculinum, a pe- 
culiar feature in the family. Its female apparatus shows close agree- 
ment, as does also the location of the genital pores, with that of the 
genus Stylochus. But there is, however, an indistinct trace of a 
ductus vaginalis. 2) Kaburakia from Vancouver has a ductus vagi¬ 
nalis of the same type as that of the genera Cryptophallus and 
Bergendalia, but is easily separated from these through the occur- 
rence of well-developed stout tentacles and through the organization 
Vidensk. Medd. fra Dansk naturh Foren. Bd. 79. 7 
