292 104 



the body, I do not know; when the animal swims, it seems as if it is wholly with- 

 drawn into the body. At all events the ductus seminalis may be able to be elongated 

 and again abbreviated in a very high degree. Size of male 50 ft, of female 350 — 400 //. 

 Time 25/VlII 21. 



As mentioned above, only Hudson has seen the male; our descriptions and 

 drawings agree rather well; I have however never seen such long setæ as Hudson 

 describes and figures; also the penis is much thicker. It will be understood, that the 

 male is extremely reduced; of the six "limbs" only three are present and these onlj' 

 transformed into very short, fleshy protuberances with a few stiff bristles. The two 

 ciliated straight processes behind on the body of the female are totally absent in 

 the male. 



In the sexual period in August the males are extremely common. 



General remarks. 

 Common to all the males belonging to this family is the extreme reduction; 

 the wheel-organ consists of a wreath of cilia, encircling a disc covered with cilia, 

 in Triarthra provided with a proboscis-like organ, but dorsal and lateral antennæ have 

 not been observed. There are two eyes, a brain. Of inner organs only the testis has 

 been observed. Perhaps in all species the hindpart of the bodj' is acuminated during 

 the paring process and then used as a penis. 



Melicertidæ, 



Of the Melicertidæ genera the males are quite unknown in the genera Oecistes, 

 Limnias and Cephalosiphon; also the males of most of the other species are very 

 badl}' described; well known is only the male of Lacinularia socialis, described by 

 Hamburger. 



Conochilus volvox Ehrbg. 



Male: Cohn 1862, p. 205. 

 Hlava 1908, p. 28. 

 Tab. XV, fig. 4—5. 



CoHN (1862, p. 205, Tab. 21, fig. 16—19). 



Die Gestalt lässt sich mit einem langen Sack vergleichen der vorn abgestumpft ist, nach 

 hinten kreiseiförmig sich etwas verjüngt. Das vordere Kopende trägt den flimmernden Wim- 

 perrand, der jedoch weniger ausgearbeitet ist, wie bei den Weibchen;., der Stiel und Fuss 

 läuft in einem Wimperbuschelaus. Verdauungsapparat fehlt ganz; das Wassergefäss system wurde 

 nicht deutlich, ist aber wohl vorhanden; Gehirn grosz, eiförmig; zwei rothe Augen mit brech- 

 ender Linse und Pigmentuniliüllen. Ein grosser birnförmiger Hoden mit den Spermatozoiden 

 vollgestopft. Der Hoden führt in einen Samenleiter, der nach aussen in einen besondern Penis 

 mündet; Höhle und liinteren Rand desselben flimmern. 



Hlava (1908, p. 28, fig. 9 D). 



"Das Manchen ist klein walzenförmig. Die Krone ist einfach, in der Mitte des Räder- 

 organs erhebt sich ein stumpfer, zwei hellrote Augen tragender Kegel; die Augen sind mit 



