The family Koellikeriadae. 157 



Seen in the first mass in that tlie moutli opening is terminal 

 guarded by a pharyngeal bulb and extending into a short Oeso- 

 phagus which quickly bifurcates. The nervous ganglia are very 

 distinct and at their level just behind the pharynx is the opening 

 of the vas deferens which is not provided with any especially mus- 

 cular cirrhus, Traced back through the neck of the worm the vas 

 deferens continues as a thickwalled tube and is spirally twisted. 

 No uterine canal is visible. No abdominal sucker is found although 

 an indefinite pink staining mass with numerous scattered nuclei is 

 visible at about the point where it was found in the other worm. 

 After a quite long course during which it passes back into the cen- 

 tral part of the tangled coils without showing any evidence of the 

 presence of an accompanying uterus, there appears a lateral pear 

 shaped sac which is tilled with spermatozoa and wliich from its 

 connection with the vas deferens must be regarded as a seminal 

 vesicle or reservoir. From that point the vas deferens becomes con- 

 nected with the abundantly folded and convoluted testis, It has 

 not been possible to make out with certainty whether in each worm 

 all these testicular masses are connected. In the other cyst there 

 were numerous disconnected masses. In this one those connected 

 with the vas deferens appear to be continuous but other separate 

 testicular masses appear in the field of the microscope in other 

 coils and probably belong to the second worm entangled in this mass. 

 At the other edge of the section, that is in the area of 

 attachment where the worm was somewhat torn there is a neck-like 

 elongated structure containing the muscular uterus and two intestinal 

 canals. This was broken before the extremity was reached but it 

 corresponds exactly with the neck found in the first cyst and must 

 be regarded as belonging to a second head. The uterus is muscular 

 and can be traced back as a thickwalled tube through coil after 

 coil in the main mass. It is füll of eggs. No vas deferens is found 

 in this Prolongation nor any ventral sucker. Probably, however, 

 this latter would have been in the part which was broken oft". 

 The rest of the coils which seem to belong to this head contain the 

 large uterus with many eggs, ovaries and vitellarian cord but as 

 mentioned before no definite shell gland nor any place at which 

 these canals form a conspicuous union could be found although the 

 whole series was searched carefully. Such a connection must be 

 present but it must be v^ery difterent from that seen in the other 

 mass for other wise it could not possibly escape attention. 



Zool. Jahrb. XXXIX. Abt. f. Syst. 11 



