Crustacea Copepoda. Il. 
By 
H. J. Hansen. 
Copepoda Parasita. 
Introduction. 
efore entering on the subject of the present paper I may refer to “Introductory Remarks” in “Crustacea 
Malacostraca I’’ published in 1908, because they contain various statements that need not to be 
repeated here. In that chapter I explained the limits of the area investigated by the “Ingolf’’ and other 
Danish expeditions to our northern dependencies; the principal sources (apart from the “Ingolf’’) for the 
material examined were enumerated, and the principles followed as to “occurrence” and “distribution” 
were laid down. Zoologists wishing to get some information on these and allied topics may find them in the 
paper mentioned. 
The present paper comprises not only the Copepoda parasites on fishes, Crustacea Malacostraca, 
and Annelida, but also the typical semi-parasites, viz. the family Asterocheride sens. Giesbrecht, and besides 
all forms living as commensals or parasites within Ascidize; furthermore the Monstrilloida, which are endo- 
parasites excepting as adults, are included, while such pelagic Copepoda which are only surmised to be semi- 
parasites (as Coryceus, Oncea, etc.) are omitted. 
Our earlier knowledge of the parasites on fishes, Annelida and malacostracous Crustacea living near 
Greenland was rather good, but as to semi-parasites and commensals it was extremely poor. In his “Con- 
spectus” (1913) K. Stephensen put together all what was known; he enumerates as “Copepoda marina para- 
sitica’”’ 40 species. Two of these must be cancelled as synonyms, and a third form (Canthocamptus? Hippolytes 
Kr.) is certainly neither parasite nor commensal; thus we get in all 37 species, one of which belongs to the 
Notodelphyoida, while 36 are real parasites; later on Stephensen has added a species of Monstrilla. From 
the seas at Iceland and the Feroes a low number of parasites on fishes was known, and 3 among them were 
unknown from Greenland. The result is that about 41 species of parasites, semi-parasites and commensals 
were known from the “Ingolf’’ area. 
In the present paper I0I species are enumerated, all, excepting 3 not seen by me, preserved in the 
Copenhagen Museum; 29 species are established as new to science. The “Ingolf’’ has gathered 43 species, 
The Ingolf-Expedition. III. 7. iL 
