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completement hors de doute dans son beau travail sur Rhizorhina ...« This requires a 
comment. I have proved the following facts. The males of Rhizorhina and of Herpyllobius 
are not the larve. The larva fastens itself to the female by a gluey substance, after which 
all its muscles etc. are dissolved; the limbs are emptied of their contents and the whole 
plasma of the larva contracts and surrounds itself with a new skin, thus forming a male 
without limbs, mouth or other external organs, and without visible internal organs except testicles 
and their efferent ducts which gradually develop themselves. In the Rhizorhina this male 
remains inside the skin of the larva, pushing its remarkable spermatic ducts out through 
the hole in front of the mouth of this dead case. In the Herpyllobius the skin af the 
larva bursts, the male fastens itself with its front, and the spermatic ducts proceed (behind 
the attached end) through the split produced by the bursting of the larval skin. So in 
both cases the male is transformed to such a degree as to render a morphological orientation 
rather uncertain; at all events, we can no longer speak of »le voisinage de la bouche», as 
there is no mouth at all. This description of the male of Herpyllobiidee will also give a 
sufficient idea of the immense difference between this animal and the males of Choniosto- 
matidee which, moreover, fix their spermatophores on the females in the usual way. 
The authors continue: »Chez tous les Spheronellide, les canaux génitaux miles 
servent aussi a l’excrétion d'une substance cémentaire avec laquelle le male se fixe sur la 
femelle dune facon plus ou moins durable. Ce role nouveau et ces connexions singuliéres 
des canaux génitaux constituent a coup str le trait le plus saillant de la morphologie de la 
famille des Spheronellide, telle que nous la comprenons«, namely Choniostomatids and Her- 
pyllobiide together. The authors are bold indeed; they do not hesitate to suggest one 
hypothesis after another, the second more erroneous than the first. Now, to begin with 
Herpyllobiide, who has said anything that could justify the statement that the genital organs 
of the male secrete the viscous substance by which the animal attaches itself? The authors 
have seen nothing themselves, and they cannot base their statement on my essay about 
Rhizorhina, as I maintain that the larva of this animal attaches itself by a gluey matter 
proceeding from the mouth before the male is developed and before there is any indication of 
genital organs. The male keeps inside the skin of the larva, which remains attached to the 
female, and no further fixation takes place’). How then must we qualify the sentence the 
authors pronounce as if it were proved? To put it mildly, we can only call it a product 
of imagination. — We shall now turn to the second division of their »Spheronellide«: the 
Choniostomatidz, and here again we shall have an opportunity of considering their above 
quoted lines in italics: »Les canaux excréteurs des glandes génitales males débouchent dans 
la partie céphalique de l’animal et dans le voisinage de la bouche«. 
‘) In the Herpyllobius the male attaches itself a second time by its front end, but the genital aperture 
is found at some distance behind this fixation (Entom. Meddel. |. c. p. 230). 
3° 
