816 REPORT OF COMMISSIONER OF FISH AND FISHERIES. [98] 



portant differences between these specimens and C. eschrichtii. The 

 points of resemblance are so many, however, that I do not feel justified, 

 at present, in making a new specific name. 



Acanthobothrium Van Beneden. 



Bothriocephali {Onchohothrii) spec, Rudolphi. 

 Calliobothrii spec, Diesing. 



Body articulate tseniseform. Head separated from the body by a 

 neck, quadrangular. Bothria four, opposite, attached to head by antero- 

 dorsal side, each with two transverse costse on face, and armed in front 

 with two bifurcate hooks, and surmounted in front of hooks by a tri- 

 angular pad, bearing a supplemental disk which is capable of assuming 

 diverse forms. Genital apertures marginal. 



The genus Acanthobothrium was established by Yan Beneden to ac- 

 commodate forms whose scolices resemble those of Calliobothrium, but 

 which bear forked instead of simple hooks. To the genus Acantho- 

 bothrium he referred the species A. coronatum (Bothriocephalus coronatus 

 Rud.), and a species which he named in honor of Dujardin, A. dujardinii. 

 The former species has since been referred to the genus Calliobothrium by 

 Diesing, whose classification is accepted by Yon Liustow. Yan Bene- 

 deu's species, A. dujardinii, is placed in a new genus by Diesing, and 

 is now known as Prosthecobothrium dujardinii. 



The genus Acanthobothrium is thus briefly characterized by Yan 

 Beneden : 



The four bothria armed each with two hooks united at their base and forked at 

 the apex. 



I have been led to restore the name Acanthobothrium on account of a 

 small species, the scolex of which agrees very closely with A. coronatum, 

 and the strobile with A. dujardinii Yan Ben. (Prosthecobothrium dujar- 

 dinii Dies.). According to this view the species G. coronatum should 

 be henceforth known as Acanthobothrium coronatum Rud. 



Acanthobothrium paulum, sp. nov. 



[Plate viii. Figs. 1-7.] 



Head subquadrate. Bothria four, opposite, oblong, faces hollowed 

 out and boat shaped, borders usually somewhat inflexed, with two 

 transverse costae, the anterior costa a little back of the middle of the 

 bothrium, the other near the posterior end. The posterior ends of the 

 bothria from about the anterior costa free and versatile, narrowed and 

 bluntly rounded, each bothrium with two forked hooks at anterior end. 

 The bases of these hooks meet on the median line of the bothrium. 

 The inner prongs are the longer, the distance between them is about 

 equal to the distance between two prongs of the same hook. The outer 

 prongs bend outwards and backwards sharply. The bases of the hooks 

 are slender, about same diameter as the prongs, and are not quite as long 



