SEA-FISHERIES LABORATORY. 337 



had occurred in the lower third of the sewer and, as it was 

 impossible to clear the pipe, the latter had been cut; it 

 was, however, still found impossible to remove the block, 

 and a further cut was made in the pipe about 500 to 600 

 yards from the outfall. The crude sewage was, therefore, 

 flowing from this latter break in the pipe at the time when 

 we made our visit. 



The ground round the pipe for the greater part of the 

 length of the latter consists of hard clean sand, which 

 affords no holding for the mussels. But the vertical and 

 horizontal wooden piles supporting the pipe are covered 

 with a thick growth of the shellfish, and here and there 

 the shellfish were attached to the pipe itself. The mussels 

 are mostly large, well-nourished animals with fairly 

 clean shells. They were generally well over the gauge 

 size, and, apart from the question of their contamination, 

 appeared very suitable for food or bait. 



The sample for analysis was collected by taking one 

 mussel at regular intervals from the vertical piles on the 

 Eastern side of the pipe all the way up from the outfall. 

 Those which were collected from the piles in the vicinity 

 of the break in the pipe were kept apart from the others 

 and examined separately. The primary inoculations were 

 made on the morning of the 19th. The method of analysis 

 was that previously adopted in similar cases, and consisted 

 in inoculating about 0*1 to 0'25 cc. of the contents of the 

 stomach of each animal on separate plates of neutral-red, 

 bile-salt, lactose agar ; and in further testing the colonies 

 formed on this medium for Bacillus coli communis by their 

 reactions on various sugar media. In every case 

 inoculations were also made to determine the presence or 

 absence of the spores of an anaerobic bacillus, presumably 

 Klein's B. enteritidis sporogenes. The results were as 

 follows : — 

 Y 



