[95] NOTES ON ENTOZOA OF MARINE FISHES. 813 



The following detailed measurements were made on living specimens: 



Dimensions. 



No. 1. 



Length 



Length of head 



Length of bothria from hooks to posterior end. 



Breadth of bothria 



Length of hooks 



Diameter of neck 



Length of last segment 



Breadth of last segment j 



mm. 

 9.00 



.60 



.20 



.20 



1.00 



.60 



No. 2. 



mm. 



6.00 

 .90 

 .64 

 .34 

 .24 

 .24 



1.00 

 .32 



In No. 1 there were six large proglottides preceded by five smaller 

 ones and a few indistinct ones near the head. In No. 2 there were fif- 

 teen distinct segments. The first six or eight of these were only mod- 

 erately distinct, merging into fine trausverse wrinkles near the head. 

 In another specimen the five posterior segments were larger than the 

 others and were preceded by nine smaller segments, gradually dimin- 

 ishing towards the head, where they merged into indistinct segments, 

 indicated by trausverse lines. The posterior segments are, in general, 

 elongated, loosely attached to each other, and separating easily from the 

 strobile. Usually there are from three to five mature segments. Six 

 is the greatest number observed on a single strobile. 



The greatest difference observable between these specimens and Van 

 Beneden's G. eschrichtii is in respect to the dimensions of the posterior 

 segments. The dimensions given by Van Beneden for G. eschrichtii 

 are: Length, 4 to 5 mm j length of bothria, .G mm ; length of hooks, .l mm ; 

 breadth of neck, ,2 mm ; length of free proglottis, 8 to 9 mm . A compari- 

 son of these measurements with those given above will show that the 

 principal difference is that which exists between the posterior segments 

 of my specimens and the free proglottis of Van Beueden's description. 



On one occasion I found a large proglottis associated with some indi- 

 viduals of these species which I at first thought might prove to belong 

 to G. eschrichtii. Upon comparing it carefully with posterior segments 

 of G. eschrichtii and of Rhynchobothrium bulbifer I found that it be- 

 longed to the latter. I am therefore tempted to believe that Van 

 Beneden has mistaken the free proglottis of some other Cestod for that 

 of G. eschrichtii. I have frequently found mature segments on the 

 longer strobiles of G. eschrichtii, as well as free proglottides, from which 

 the large ova were issuing, but have never found them to exceed about 

 1.5 mm in length, while on the other hand, associated with them, I have 

 ofteu found specimens of R. bidbifer with posterior segments and free 

 proglottides measuring 5 mm and 6 mra in length. 



The description given above is perhaps enough to render identifica- 

 tions of this species certain, but as Van Beneden 7 s description would 

 indicate that there may be some constaut differences between his speci- 



