■906 



SCIENCE. 



[N. S. Vol. IX. No 235. 



moves several loug scales of the inner in- 

 volucre by a clean cut close to the re- 

 ceptacle, thus exposing the plumed akenes, 

 and then seizes a mouthful of these between 

 the plumes and ' seeds,' lopping oflf the 

 plumed pappus and swallowing the ' seeds.' 

 The mutilation of the involucre by the 

 sparrow's beak can be seen until the flower 

 stalk dries and falls. Fully three-fourths 

 •of the dandelions that bloomed on the De- 

 partment grounds during April and May, 

 1898, were mutilated by birds. 



The English sparrow, in spite of the ser- 

 vices it renders in consuming weed seed, is 

 a pest because of its despoiling buildings, 

 and because of its extensive pillaging of fruit 

 and grain. The native sparrows, on the con- 

 trary, have no such noxious habits, and are 

 much more eflicientas weed-seed destroyers. 



The several species of goldfinches are 

 equally beneficial. The American goldfinch 

 confines its attacks almost entirely to the 

 Compositce; the thistle, ragweed and dande- 

 lion being its fiivorites. Last October I 

 observed a flock of fifty on a New Hampshire 

 farm. A bird would alight on a bull this- 

 tle and the pappus would float away as it 

 feasted. Under a thistle head I found over 

 a hundred empty akenes that had been 

 split open on one side and had their seeds 

 removed. These goldfinches alighted, sev- 

 eral at a time, in a single ragweed plant 

 and fed so busily that I could approach 

 within a few feet of them. On another daj^ 

 this flock of birds fed upon the evening 

 primrose. According to Mr. H. C. Ober- 

 holser the goldfinch also feeds upon beggar 

 ticks (Bidens frondosa) and milkweed {As- 

 clepias syriaca) . 



Dr. E. V. Wilcox has observed American 

 goldfinches in Montana feeding in flocks of 

 fifteen to twenty on the wild sunflower, 

 which is a very bad pest in the West. In 

 the same State he observed Juncos and red 

 poll linnets eating the seeds of the Eussian 

 thistle. 



The goldfinches and native sparrows are 

 more beneficial to agriculture than a num- 

 ber of other species, such as the English 

 sparrow and blackbirds, which at times in- 

 jure grain and fruit, but there are, how- 

 ever, iu the work of weed-seed destruction 

 some fifty species of birds engaged, and the 

 number of species of weeds which they tend 

 to eradicate amounts to more than three 

 score. 



Sylvester D. Judd. 



Department op Ageicultuee. 



THE BIOLOGY OF THE GREAT LAKES. 



Science for July 1, 1898, contained a no- 

 tice by Dr. H. M. Smith, of a proposed 

 Biological Survey of Lake Erie to be car- 

 ried out under the auspices of the United 

 States Commission of Fish and Fisheries. 



Unfortunateljr, none of the work of the 

 season of 1898 could be entered upon until 

 the middle of July, audit was discontinued 

 about the first of September. Since the 

 work outlined in the second paragraph of 

 Dr. Smith's notice is of such a character 

 that it must be carried on continuously, 

 it must wait for the establishment of a per- 

 manent biological station on the lakes. 



The work that could actually be under- 

 taken was that outlined in the third para- 

 graph of the notice. The shortness of the 

 time (4-6 weeks) did not permit results to 

 be reached in many of the problems under 

 investigation ; so that the results of the 

 summer's work so far published are con- 

 tained in three papers by Dr. Jennings, a 

 brief notice of the occurrence at Put-in-Bay 

 of Trochosplioira solstitialis, contained iu 

 Science, October 21, 1898, and two papers 

 on ' The Motor Reactions of Parwnoscium ' 

 and the ' Laws of Chemotaxis in Parame- 

 cium ' in the American Journal of Physiology, 

 May 1, 1899. Progress was, nevertheless, 

 made in all the other lines of work. Some 

 of the results are now awaiting publication 



