21 
niostomatide. The differences between the families will be shown most clearly by giving a 
short description of each. In the Choniostomatide both sexes possess af least antemnule, a 
mouth with mandibles, maxillule and maxille, and the males have always maxillipeds, and 
they fix their spermatophores on the females in a normal way. The female deposits its eggs 
in one or two free lumps or, in most cases, in ovisacs, of which at least four or five and 
sometimes more than twenty are found; the larve attach themselves by an adhesive plate 
on the forehead and — whether passing through the pupa stage or not — develop them- 
selves into animals of either sex. In Herpyllobiide both sexes lack antenne, mouth and 
appendages; the females project a mysterious body or two ramified tubes into the host 
and draw nourishment through these organs. The males project from the anterior part of 
their body in advance of the mouth of the larval skin two long spermatic ducts, which are 
formed by a secretion in the genital organs, and through these canals nearly the whole sub- 
stance of the body, having been transformed in the service of propagation, is transferred 
into the female. The female has two ovisacs; the larva attaches itself by a gluey sub- 
stance proceeding from the mouth, and is transformed into a limbless male or female. In 
the latter case the animal forms a stalk which pierces the skin of the host, inside which 
it dilates and develops into the above-mentioned organ of nutrition. — Whereas the Cho- 
niostomatide, on the whole, fit in well among the other families of parasitic Copepoda, the 
Herpyllobiids remove themselves from the others by a series of very peculiar features, 
occupying a more isolated position than any other of the families. 
This, I hope, will be sufficient to prove that the juxtaposition by the authors of 
the two families in question as sub-divisions of one family, is contrary to all sound classi- 
fication. I think also that sufficient light is thrown on the characters and hypotheses of 
the authors. The present work being a kind of monograph, I found it necessary to write 
this rather detailed critique of their publication. However, this task has not been at all 
pleasant to me, because in another branch, the Epicaridea, they have published works 
which must be considered the principal sources of our knowledge about important groups 
belonging to this large and difficult family. In the interest of the authors and of carci- 
nology, as well as for my own sake, I wish they had not published their four, at least not 
the two last of their contributions (the preliminary note in 1893 and their final essay 
1895) about Choniostomatide. It would indeed have been very natural to postpone the 
publication of their two last papers, as their material of these animals (whose manipulation 
presents considerable technical difficulties) was rather scanty, and as, even as early as 1891, 
they know that I was preparing a work based on very abundant material. (L need scarcely 
add that the fact of their publishing a report about one species previously to myself affects 
me very little; indeed I might easily have secured this priority by some »preliminary note«). 
If, nevertheless, they were intent upon describing their few animals, their researches might 
and ought to have been much better, and they ought to have abstained from filling up real 
