115] PROTEOCEPHALIDAE—LA RUE 115 



monis Wartmanni being a descriptive name of three parts is not avail- 

 able. It is not necessary to discuss the question as to whether it was 

 sufficiently described to give it any standing. T. Froelichii was evi- 

 dently based on the same description as the T. salmonis Wartmanni for 

 Gmelin (1790) gives little more than a catalogue of species and refers 

 to Froelich's (1789) work. Since the combination Taenia longicollis 

 Rudolphi is no longer the proper one with which to designate this 

 species, the generic name Proteocephalus being used to designate the 

 genus, it is here suggested that the proper combination for the designa- 

 tion of the species is Proteocephalus longicollis (Zeder). In a recent 

 article the writer, La Rue (1911:475), overlooked the priority of Ze- 

 der 's Alyselminthus longicollis over Rudolphi 's Taenia longicollis and 

 hence in a list of species of Proteocephalus gave the credit for the P. 

 longicollis to Rudolphi instead of Zeder. 



The description is based on von Linstow's (1891) paper. His ma- 

 terial was collected from Osmerus eperlanus which is one of the hosts 

 in which Rudolphi found Taenia longicollis. 



Von Linstow reports that his largest specimen measured 46.4 mm. 

 long by a maximum breadth of 0.99 mm. At its posterior end the worm 

 measured 0.83 mm. broad. The scolex measured 0.43 mm. broad, the 

 neck 0.3 mm. broad by 3.2 mm. long, first proglottids 0.43 mm. long by 

 0.71 mm. broad, proglottids at end of first third of strobila 0.53 mm. 

 long by 0.99 mm. broad. The proglottids gradually increase in length 

 until the last are 1.03 mm. long by 0.83 mm. broad. The end-proglottid 

 is triangular and drawn out posteriorly. The specimen was incom- 

 pletely developed. The four suckers have a circular outline, 0.12-0.14- 

 0.18-0.19 mm. in diameter. A fifth apical sucker has a diameter equal 

 to one-half that of the others. 



The excretory system is made up of two large lateral vessels, one 

 on either side just outside of the vitellaria, and six smaller vessels, three 

 on either side lying dorsal to the larger vessel. All excretory vessels 

 are greatly twisted and many anastomoses connect them. About 0.08 

 mm. anterior to the posterior margin of each proglottid a transverse 

 commissure connects the ventral excretory vessels. The latter measure 

 0.019 in diameter and the smaller vessels about 0.0078 mm. In the 

 region just posterior to the suckers there is a circular commissure of 

 excretory vessels from which branches extend anteriorly into the head. 

 All the main vessels discharge into a small vesicle at the posterior end 

 of the end-proglottid. 



The genital pore is marginal, irregularly alternating, and situated 

 near the end of the anterior one-fourth of the proglottid (Fig. 167). 

 The testes are large, spheroidal, measuring up to 0.09 mm. in diameter. 



