144 



SCIENCE 



[N. S. Vol. XLV. No. 1154 



The Relations of Mollushs to Fish in Oneida 

 Lake. By Frank Collins Baker. Tech- 

 nical Publication ISTo. 4, New York State 

 College of Forestry at Syracuse University. 

 Pp. 366. 



The New York College of Forestry, under 

 the leadership of Dr. Hugh P. Baker, takes a 

 broad view of the subject in including not 

 only the waters conserved by the forests, but 

 also their animal life and economic resources. 

 The present volume is concerned primarily 

 with the moUuscan food of fish, but a large 

 part of it discusses the relations of mollusks to 

 the rest of the fauna and the flora, the dis- 

 tribution and associations of species and other 

 topics interesting to zoologists concerning 

 themselves with fresh-water faunas. 



It appears that mollusks form 31.5 per cent, 

 of the food of 25 of the most important food 

 and game fishes of the state. About half of 

 the species of fish found in Oneida Lake are 

 in some degree mollusk feeders. The fauna of 

 the lake comprises upwards of 62 species and 

 varieties of shellfish, nearly all of which are 

 known to contribute to the piscine menu, but 

 in varying degree. The little clams of the 

 family Sphseriidse appear to be a favorite 

 article of diet, also such diminutive gastropods 

 as Valvaia and Amnicola, as well as the larger 

 Physa and Planorhis, all these appearing in 

 the food lists of many species. The large 

 mussels, Unionids, are used by a smaller nmn- 

 ber of fishes. The whitefish, catfishes and 

 pumpkinhead are notable for the large number 

 of species of mollusks eaten. 



The areas rich in life are confined to the 

 shallows along the shores, usually not exceed- 

 ing three fourths of a mile wide and twelve 

 feet deep, afl^ording an area of approximately 

 8,343 acres for feeding and breeding grounds 

 for fish. In deeper water, vegetation is scarce 

 or absent, and only scattered individuals of 

 three species of mussels were taken with the 

 crowfoot dredge. Possibly the total absence of 

 gastropods was due to the form of dredge used ; 

 yet the same poverty of deep water was noted 

 by Miss Maujy in Cayuga Lake. It seems 

 likely that the mollusks of these post-glacial 

 lakes have not had time to become adapted to 



deep water conditions, as they have in the 

 Swiss lakes and many other bodies of fresh 

 water. 



No general valuation of the total molluscan 

 fish food of the lake is attempted, but there 

 are some interesting estimates of limited areas, 

 from counts made of selected plots of a foot 

 square. A bowldery station 300 X 500 feet 

 has a mollusk population of Y,650,000 indi- 

 viduals. On a sandy bottom area 1,000 X 500 

 feet the counts indicated 65 million. Finally, 

 in the outlet, where there is a uniform area of 

 fully 3,500 X 500 feet, there are estimated to 

 be 304J million mollusks. 



The chief species are illustrated by photo- 

 graphic figures. Mr. Baker's work is well done, 

 as we should expect from his long experience 

 with freshwater mollusks, and his excellent 

 volume on the North American Ljrmnaeas. 

 The book will be found a useful addition to 

 the literature of freshwater zoology. 



Henry A. Pilsbby 



Academy op Natural Sciences op 

 Philadelphia 



SPECIAL ARTICLES 



THE OVERLAPPING OF THE LEAF SHEATH AND 



ITS LACK OF VALUE FOR DESCRIPTIVE 



BOTANICAL LITERATURE 



During the crop season of 1916 the writers 

 grew, at Texas Substation No. 8, Lubbock, 

 Texas, imiformly tall and dwarf plants of milo 

 from the same seed, by varying the time of 

 planting and the environmental conditions. 

 Measurements were secured from both the tall 

 and the dwarf plats, by taking ten consecutive 

 main plants in an average row and recording 

 the internode and sheath lengths. The total 

 number of internode and sheath measurements 

 amounted to 78 in the tall group and 93 in the 

 dwarf group. The results showed the mean 

 internode length in the tall group to be 13.33 

 dr .061 centimeters, as against a mean inter- 

 node length in the dwarf group of 6.88 =t .048 

 centimeters. The mean sheath length was 

 17.46 dr .050 centimeters in the tall and 15.95 

 =i= .026 centimeters in the dwarf. 



Tall and dwarf plats of kafir were also grown 

 from the same seed and a similar set of meas- 

 urements, totaling 106 in the tall and 100 in 



