55] PROTEOCEPHALIDAE — LA RUE 55 



Benedict (1900:355-365) described some cestodes which had been 

 collected by Dr. H. B. Ward while engaged in a biological investigation 

 of Lake Michigan under the auspices of the Michigan Fish Commission 

 during the summer of 1894. The hosts were Coregonus nigripinnis, C. 

 prognathus, and C. artedi. Benedict who had for comparison some 

 specimens identified by Zschokke as Taenia ocellata Rud. (probably P. 

 fallax La Rue) thought his material and Zschokke 's specifically iden- 

 tical. He, however, called attention to the fact that Zschokke 's speci- 

 mens had been nearly dried out in transit and consequently were almost 

 ruined for study. Accepting Kraemer's statement that Taenia filicollis 

 Rud. and T. ocellata Rud. were identical he used the name Proteocepha- 

 lus filicollis (Rud.) to designate his form. Later he discovered that the 

 name Taenia ocellata Rud. had page precedence in the original paper 

 by Rudolphi (1803) and in a foot-note he called attention to the fact 

 that the name Proteocephalus ocellata (Rud.), mis-spelling for ocella- 

 tus, should be used to designate the form. La Rue (1911:477-478) 

 distinguished this species from P. filicollis and described it as a new 

 species P. exiguus. 



Careful examination of prepared specimens from some of the same 

 lots used by Benedict in his research and a study of one of his slides 

 together with a comparison of these with specimens which Zschokke had 

 sent to Dr. H. B. Ward under the name of Taenia ocellata — (now No. 

 09.9 in Professor Ward's collection) — has convinced the writer that Bene- 

 dict's species is a new one. La Rue (1911) proposed for it the name 

 Proteocephalus exiguus La Rue by reason of the small size of the indi- 

 viduals. Benedict worked out the morphology of the form quite cor- 

 rectly and probably would have given due weight to the difference be- 

 tween his own and Zschokke 's specimens had the latter been in good 

 condition. 



This species is based upon the work of Benedict (1900:355-365) 

 and upon a further examination of, and collection of, data from certain 

 lots of alcoholic material in Dr. H. B. Ward's collection from which 

 Benedict secured his specimens for study. These bottles bear the labels 

 "Long-jaw, stomach. Charlevoix Jy. 16, '94". "Ch. 7 c, Cestodes, Etc. 

 Stomach Black-fin Charlevoix, Jy. 16, '94." "Ch. 3 c, cestodes. Core- 

 gonus Artedi Jy. 12, '94". Slides have been prepared from the first 

 two lots. 



The specimens which were examined carefully by the writer ranged 

 in length from 9-10-15 mm. Benedict found the length to vary from 

 12-16-25 and one specimen only attained the length of 38 mm. This 

 one case seemed to have been due to an extreme attenuation for the neck 

 was 7 mm. long. This attenuation may have been caused by the method 



