18 



d'antennes, meme structiue de I'appareil buccal avec la ventouse si sp6ciale et les appendices 

 transform^s en stylets, meme disposition des merabres thoraciques, etc. 



Les jeimes individus surtout pr^sentent ime ressemblauce extraordinaii'e et indiquent 

 uettement la parents des deux groupes. 



Mais il est un caractere du male sur lequel nous d6sirons particulierement attirer 

 I'attention, parce qu'il est tres exceptionnel et qu'on ne le retrouve dans aucune autre 

 famille de Cop^podes, en dehors des C]ioniosfomatince et des Herpyllohimce. 



Les canaux excreteurs des glandes genitales males debouchetit dans la partie cepha- 

 lique de V animal et dans le voisinage de la bouche«. 



Let us examine this a little more closel3^ Though the authors think that the 

 larvae in particular show »une ressemblauce extraordinaire «, we find that these larvae, which 

 indeed may be said to be in the first (7yctoj>s-stage , resemble each other less than the 

 larvae of a Choniostomatid and of an AcJdJteres respectively, according to the illustration 

 given by Clans (Zeitschrift wissensch. Zoologie B. XI, Taf. XXIII, fig. 5). At any rate, 

 the likeness between the mouths of the larvae of a Bhigorhina and of that of a Choni- 

 ostomatid is not so great as the authors seem to tliink, and it is certainly much smaller 

 than that between the mouth of a larvae of the last-mentioned group and e. g. of a larva 

 of Pennella. The maxillae of the two groups deviate much from each other in shape and 

 position etc. Several great differences between the males of Choniostomatidae and of Her- 

 pyllobiidae have been pointed out above, and we shall soon mention more. The differences 

 between the adult females also seem to be so great that we are struck by the astonishing 

 boldness of the assertion that: »en raison de la degradation, toute comparaison peut sembler 

 d6pourvue de valeur«. In the former type, the Choniostomatidae, the female possesses at 

 least the antennulae, a well-developed mouth with mandibles, maxillulae and maxillae; in 

 the latter, the Herpyllobiid;*, the body has no vestige of these organs or of any limbs, and 

 in the three genera which are examined so thoroughly, that our knowledge about their 

 nutrition is perfectly reliable, we know that it takes place through a large mysterious body 

 (in Herpgllohius and Silenium) or through an e(iually mysterious tubular system [Rhizo- 

 rhina) which is found in the body of the host, and which has a most curious, hitherto 

 unexplained development (comp. my essay about Rhizorhina). Indeed, I can find no other 

 likeness between the females of these families than the small size of their bodies, their sub- 

 globtdar or oval form., and their two genital apertures, and as this last character seems 

 to be common to all parasitic Copepoda, we might as well pass it over. 



But still more objectionable is the statement printed in italics, that in the males 

 of both families the genital aperture is found on the head near the mouth. I shaU begin 

 by speaking of HerpyllobiidaB. The authors substantiate their opinion in these words: »Ce 

 caractpre, tellement extraordinaire que nous ne I'avions signals qu'avec reserve dans notre 

 6tude sur Aspidoecia et dans nos recherches plus r6centes sur Salenslci/a, Hansen I'a mis 



