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and forty specimens belonging to thirty-eight species infested with Choniostomatide, but neither 
on these, nor on any other of the thousands of individuals belonging to these thirty-eight 
species, have I found one single Epicarid. So we have done with thirty-eight of my species 
of Choniostomatide, and of the five remaining species two may be passed over, viz. the species 
of the genus Mysidion, for neither I nor any other author have found any Epicarid in the 
marsupium of the hosts of Mysidion, viz. the genera Erythrops and Parerythrops. Only on 
the outside of the body of the species belonging to the genus Hrythrops, and in the branchial 
cavity of two species of Hippolyte, others as well as myself have found altogether three 
species of Choniostomatidz, and at the same time species of Epicaridea. As a rule the 
animals of each order were found on separate specimens; in one case observed by myself, 
and in one case mentioned by Giard and Bonnier, animals of both orders were found on the 
same specimen. Still it can be proved that these two quite different types of parasites, 
though perhaps in very rare cases they may be in each others way, stand at least in no 
other mutual relation. As for Choniostoma Hansenii, I can prove that the animal itself 
produces the swelling on the carapace (comp. my special description of this animal), and in 
the only case where Choniostoma and Gyge were found on the same side under the carapace, 
a male and a still smaller female of the latter genus had lodged themselves in a large 
swelling, which was inhabited by an adult female Choniostoma with eleven oyisacs. As for 
the last of my species — Aspidoecia Normani — I have found it on twenty-one specimens 
of all five species of the genus Erythrops, but I found no Epicarid on any of these animals. 
Moreover, the occurrence of Aspidoccia, not only on the shield, but also on the exterior side 
of the thorax and on the six abdominal segments, as well as on the eyes, proves sufficiently 
that it stands in no connection whatever with Aspidophryxus, which parasite lives only 
on the carapace. 
Immediately after the paragraph criticised above the authors write: »Toutes ces 
considérations sont sans doute fort hypothétiques, mais elles penvent inspirer de nouvelles 
recherches et indiquer la voie aux investigateurs. Elles ont de plus l'avantage de rattacher 
par un lien éthologique commun les types de Copépodes si étranges qui constituent la famille 
des Choniostomatide«. This »lien éthologique« is quite broken now and will scarcely ever 
be restored. As for the first part of the quotation, I regret to say that it has indicated 
no path to me, and that, far from having been inspired by their »considérations«, I have 
been obliged to waste time and space upon proving the untenability of some unwarranted 
hypotheses. To suggest such hypotheses indeed is not very difficult, and most zoologists 
have imagination enough to invent scores of them. If productions of this kind had any real 
value, it would be easy to promote the progress of science. But I confess that, though I 
honow everybody who is capable of suggesting a theory which proves to be well founded 
and fertile in results, I have always felt and, as time goes on, feel more and more distaste 
for superficial conjectures. 
