74 



Charl. Mus. 1. c.)- A more careful consideration of this form 

 seems to indicate that its very deeply sinuate sun leaves, the dif- 

 ference in form between the shade and sun leaves and the larger 

 fruit and loose white-oak-like bark are characters which are 

 sufficiently strongly marked and of a constanc}^ to entitle it to 

 specific rank. 

 1/ Carya ovalis megacarpa n. comb. (C megacarpa Sarg. T. & S. 

 2, 2oi). An examination of material of Carya megacarpa Sarg. 

 from the type locality, Rochester, Monroe County, N. Y., shows 

 that this tree exhibits close affinity to C. ovalis (Wang.) Sarg. by 

 having the lower surface of the 5 to 7 leaflets dotted with resinous 

 globules, by having thick, glabrous, red-brown twigs, and short 

 (though larger) ovate and obtuse buds. The only distinguishing 

 characters seem to be in the fruit and buds. The fruit of C. 

 ovalis is extremely variable, Dr. Sargent having distinguished 

 four forms, of which the variety ohovatis approaches C. mega- 

 carpa. The buds also vary, becoming smaller and inseparable 

 from those of C. ovalis, and in a form from the coastal plain of 

 Georgia, a specimen of which has been examined by Dr. Sargent 

 and referred to C. megacarpa, both buds and twigs are as slender 

 as in C. porcina (Mx.) Nutt. 



REVIEWS 



Ward & Whipple's Fresh-Water Biology* 



This monumental work, to which Professor Ward in particular 

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 supervision over the writings of the other 25 collaborators, is the 

 first attempt of its kind to cover North American fresh-water 

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With few exceptions, the various groups of organisms found in 

 fresh waters are treated quite exhaustively, both in their syste- 

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 life history, and biological relations. For the most part, each 

 genus of the various groups is illustrated; while ingenious keys 



* Henry Baldwin Ward and George Chandler Whipple, Fresh Water Biology. 

 Pp. ix -f- nil. 1,547 figures. New York, John Wiley & Sons, 1918. Price 

 16.00. 



