714 PROCEEDINGS OF THE NATIONAL MUSEUM. voi. xxv. 



ITahltat. —Yoxmd. on the blue pike, Sthostethium sahnoneum Jordan, 

 in the Niagara River at Buffalo; named from its host. 



Kellicott verifies the statement of the local fishermen that during 

 midsummer when the water is warm this blue pike "gets too lazy to 

 take food; that it then gets poor and, through its inertness, becomes 

 infested with lice." Thej- are usually found on the top of the fish's 

 head, often "huddled together in heaps, so the knife may remove a 

 number at once." They occur also on the fins, but have never been 

 found in the mouth cavity. Kellicott's paper descriptive of this species 

 could not ))e found till just before this article went to the printer, but 

 the author was gratified to find in it observations confirmatory of sev- 

 eral of the habits of Argulids recorded here: 



When put into my aquarium with a small specimen of LepidfMeus osseus and some 

 minnows, they shortly located on them, fastening as before to the head and fins of 

 the gar-pike, but to any part of the minnows; these latter soon die, killed apparently 

 by the Argulus (p. 652) . 



At first these fish pursued and caught them, "but would eject them 

 with a suddenness and a queer expression of frustration that was most 

 amusing" (p. 647). 



The gar even recoiled " in evident fear from one seen approaching." 

 The removal of the scales from portions of the body surface in the 

 fish that died, a-s noted by Kellicott, is readily explained by the fact 

 already mentioned (p. 650) that the Argulids burrow in under the 

 scales to find a place where the skin is soft enough for their stings to 

 penetrate. 



Through the kindness of Mr. William E. Kellicott, son of Prof. D. S. 

 Kellicott, the author obtained a mounted specimen of this species for 

 examination, and others were found in the material so generously sent 

 from the Ohio State University. 



From these and from Professor Kellicott's own description, which 

 was found at the last moment through the aid of his son, the above 

 facts have been di'awn. 



The fused chitin rings and the elongated al)domen are distinguishing 

 characteristics of this species. 



ARGULUS NIGER, new species. 

 Plate XVIII. 

 Carapace elliptical, longer than wide; antero-lateral sinuses sharp, 

 but not deep; posterior sinus narrow and half the length of the cara- 

 pace. The entire body and half the abdomen covered by the carapace 

 lobes, which overlap across the back of the thorax. Abdomen broadly 

 ovate, on(-third the length of the rest of the body, the sides strongly 

 rounded; anal sinus narrow, cut two-thirds the length of the abdomen, 

 lobes rounded-acute; papilla? basal. Sucking disks very large and far 

 forward, one -fourth the width of the carapace; posterior maxillipeds 



