168 THE PUR SEALS OF THE PRIBILOF ISLANDS. 



16. BOTHRIOCEPHALUS sp. 



(Figs. 97-100.) 



In the materi^il collected by Lucas we find several specimens of a Both/riocephalus 

 taken from the fur seal. Lucas states that tapeworms were found in about 40 per 

 cent of the seals examined. 



To properly place this parasite would require an extensive study of the family 

 Bothriocephalidae, and for this we have not the necessary time at our disposal at 



Kg. 97. 



I'lg. 99. 



Fig. 100. 



present. We will simply remark that analogy would point to the fish as the source of 

 infection by this worm. 



The specimens collected by Lucas have been entered in the Helminthological 

 collection of the United States National Museum as Nos. 2765, 2768, 2769, 2817. 



v.— COMPENDIUM OF PAEASITES, ARRANGED ACCORDING TO THEIR HOSTS. 



This compendium covers only the genera Asearis, Uneinaria, and Bothrioeephalus,' 

 for all other parasites see voni Linstow (1878 and 1889) and van Beneden (1870 and 

 1889.) 



MARINE MAMMALS. 



We have personally examined those forms marked with an asterisk (*) under the 

 various hosts. We can not, of course, guarantee the original determinations of the 

 hosts, but taking the determinations given on the labels or by other authors we have 

 corrected the names to those now used in mammalogy. In all cases of doubt we have 

 been guided by the advice of Dr. F. W. True, of the United States National Museum. 



270. Balaenoptbra kostrata. 



Asearis simplex. 



271. Balabnoptbra sibbaldii Gray. 



Asearis simplex. 



