576 THE FUR SEALS OF THE PRIBILOF ISLANDS. 



pressure or get out of the way. They are wholly unlike starved pups, for before a 

 pup can become emaciated these worms will cause it to die from lack of blood. 



The places that favor massing of cows and fighting of bulls also promote the 

 propagation of the worms. On rocky rookeries, where pups are not massed and no sand 

 is present for worm eggs to collect in, no sickly pups and few trampled ones are to be 

 found. Many sickly pups are to be seen .on Zapadui; none are on Little Zapadni, few 

 are on Kitovi, and almost none on Zapadni Reef. 



The early dead pups from which the hair is now worn off are probably all trampled. 

 The victims of Uncinaria die from July 15 to August 15. By the latter date pups 

 affected by the worm recover or succumb. Only two dead pups not starved were found 

 after August 14 last season. 



MR. LUCAS'S NOTES. 



Three of the 6 bulls killed at Little Zapadni to-day were examined carefully for 

 parasites. Nematodes were found in one stomach. No tapeworms were present or 

 trematodes in the liver. All viscera were in a healthy condition. 



JULY 31. 

 LIVE PUPS ON POLOVINA. 



In company with Mr. Macoun I made a count of live pups on the cliff portion of 

 Polovina rookery. The total number was found to be 2,149. A number of dead imps 

 were noted, but no concurrent count could be made. It is doubtful whether a full count 

 of the dead pups is worth while this season. My impression is that the dead are about 

 as numerous as last season on this rookery, and it will probably be sufficiently accurate 

 to estimate the number as the same. This would give to this breeding ground a total of 

 2,200 pups born this season. 



One case of copulation was witnessed. The bulls give much more readily than on 

 Zapadni Reef. Many young bulls were occupying places on the breeding ground, 

 showing that some at least of the old harem masters have left. 



Some gulls were shot on the reef of Polovina Point for the purpose of determining 

 whether they were infested with Uncinaria. The sound of the shotgun startled the 

 seals for a moment. Some of the bachelors were frightened and took to the water. 

 The cows and bulls did not take fright. In the water the seals swam about the reef 

 in their curious fashion while the shooting was going on. The effect of the firing was 

 the same on the seals as it would have been on a herd of sheep, pigs, or cattle under 

 similar conditions. They roused up, were restless for a few minutes, and then settled 

 down again. 



The gulls were found not to contain Uncinaria. It was thought that they might 

 get the worm from feeding on the intestines of the dead pups. 



A number of dissections of dead pups was made by Mr. Lucas, assisted by Mr. 

 Suodgrass. Dr. Jordan and Dr. Wood examined Little Polovina. Uncinaria were 

 found in the dead pups on Polovina. 



Mr. Adams counted the Amphitheater, finding 375 cows present. He witnessed the 

 birth of a pup on Lukanin rookery. The cow, an old one, had lauded on the 27th. 



AUGUST 1. 



I visited Lukanin rookery this afternoon in company with Dr. Jordan. We 

 entered the rookery and found a good many dead pups under the cliffs. Very few of 



