REPORT OF COMMISSIONER OF FISH AND FISHERIES. 119 
human system, and a very liberal margin may be allowed in favor of 
the former. In fact, it is probable that avery large percentage of what 
might ordinarily be regarded as impurity in potable water is more 
beneficial than harmful to oysters. When the amount of free ammo- 
nia in potable water exceeds 0.01 it is generally considered te be due to 
recent sewage contamination, and the amount of albuminoid ammonia 
in a safe drinking-water should not much exceed 0.015 parts per 100,000 
parts of the water. The figures furnished by Mr. Neher’s tests may be 
summarized as follows: At the mouth of the Connecticut River, .005 of 
free ammonia and .015 of albuminoid ammonia; on a line across the 
Sound opposite the mouth of this river, .002 and .015, respectively; a 
second line somewhat further west, .005 and .01; a line opposite Matini- 
cock Point, .01 and .016; at Throgs Neck, .023 and .018. The last two 
undoubtedly show the influence of the East River. On and near the 
dumping-grounds off New Haven, Bridgeport, Norwalk, and Stamford 
the amount of free ammonia ranged from .006 to .013 and the albu- 
minoid ammonia from .014 to .019._ These dumping-places have always 
been regarded as the most serious menaces to the oyster-grounds in 
Long Island Sound, but the chemical observations fail to support that 
claim. In New Haven Harbor the free ammonia amounted to .013 and 
the albuminoid to .018, while in Bridgeport Harbor they were .02 and 
.018, respectively. 
The results of analyses made in three other bodies of water may be 
noted here for the sake of comparison, the first figures given in each 
case being those for the free and the last for the albuminoid ammonia, 
as above. Lake Ontario, 0.002 to 0.004 and 0.013 to 0.020; Oneida Lake, 
0.004 to 0.008 and 0.015 to 0.024; Thames River, England, 0.004 to 
0.176 and 0.028 to 0.035. 
It may, therefore, safely be concluded that so far as regards organic 
impurities, the oyster beds in Long Island Sound are in no immediate 
danger from that cause. The results of the dredging work also sup- 
port this conclusion, the animals taken of all kinds being generally in 
a good and healthy condition. : 
Life history of the starfish—ItIn connection with the investigation 
of starfish depredations, a special study of the embryology and life 
history of this species was begun at Woods Holl Station during the 
summer of 1889 by Prof. W. K. Brooks, of Johns Hopkins University, 
and was again taken up during the season of 1890, by one of his assist- 
ants, Mr. George W. Field. Both of these biologists have published 
_ brief notices of their preliminary results in the Johns Hopkins Univer- 
sity circulars, vol. x, No. 88, 1891.* This inquiry will be continued in 
subsequent years, and it is expected that some conclusions may be 
reached which will be of considerable practical importance. 
“On the early stages of Echinoderms; by W. K. Brooks. Contributions to the 
embryology of Asterias vulgaris (Forbesii); by George W. Field. 
