1913] Hull,— Advance of Potamogeton crispus L. 171 
ADVANCE OF POTAMOGETON CRISPUS L.— The 7th edition of Gray's 
Manual gives the range of this species as extending from Massachusetts 
to Ontario and Virginia. Here in the lagoons of Jackson Park, 
Chicago, Ill., it is very abundant. Much work is needed to keep it 
cleaned out in the spring, when its growth is most vigorous. These 
lagoons are connected with Lake Michigan, and it seems reasonable to 
suppose that this species has made its appearance here by way of the 
Great Lakes. In the lagoons of Washington Park, about a mile west, 
which have no connection with the lake, a careful search has failed to 
reveal it, and it probably does not occur. It is also found in abun- 
dance at Wolf Lake, Indiana. This body of water lies near Lake 
Michigan, and is connected with it. 
It would be interesting to know just when the plant first made its 
appearance in this region. That it has occurred here for a few years 
at least is well known to most botanists hereabouts, but I believe that 
nothing concerning it in this vicinity has ever appeared in print. 
Guided by the index to American botanical literature published 
monthly in the Bulletin of the Torrey Botanical Club, I have looked 
up every reference from 1899 to the present date that might concern 
the flora of Illinois and Indiana, both systematic and ecological 
treatises, but I have found nothing regarding this plant. ‘There may 
be a reference to it, however, in some note which the Bulletin has not 
seen fit to index. If so, I have overlooked it, but I do not believe 
that this is the case. If nothing has appeared then this may be 
regarded as an addition to the flora of both states. The advent of 
the plant, however, has doubtless been very recent, perhaps within 
the last ten years. In 1883 E. J. Hill! noted nine species of Potamo- 
geton from Wolf Lake, but made no mention of P. crispus. In 1899 
S. Coulter’s ‘Flora of Indiana’ appeared, but this species was not 
included therein. Following the publication of Coulter’s book, not- 
ably from 1900-1905, many additions to the Indiana flora came out 
in the ‘Proceedings of the Indiana Academy of Science, but this 
plant, if it occurred at all, seems to have escaped notice. My own 
acquaintance with it began in 1909. By this time it had become 
common. 
'The plant should, I think, now be found still further westward, 
especially along the Illinois and Mississippi Rivers, as it can reach the 
Illinois, which flows into the Mississippi, by way of the Drainage Canal. 
1 Bot. Gaz. 9:45-48. 1884. 
