I^O Rece7it Literature. Twi 



and Mr. Lydekker display also a masterly cominand of their subjects. 

 In short, the work thoroughly maintains the high standard of Parts I 

 and II. 



In concluding the present notice it may be not out of place to tran- 

 scribe a few remarks on special points of interest to readers of • The 

 Auk.' Thus Dr. Gadow, in his article ' Muscular System ' makes the 

 following comment: "The taxonomic value of muscles is theoretically 

 great, but very limited when put to practical test. Most of them cannot 

 be understood unless the whole group to which they belong be examined, 

 and the study of their correlations is a very complicated problem. To 

 pick out a few of the most variable muscles of the leg, and to arrange 

 birds in accordance with their mere presence or absence, without regard 

 to intermediate stages, is an easy but scarcely serious mode of investi- 

 gation, and there is no wonder that systems built on such simple notions 

 broke down. There is no reason why a dozen different kinds of birds 

 should not have lost the same muscle at different times and independently 

 of each other, and that other kinds may not lose it in future if its function 

 be no longer required or can be fulfilled by some other combination. . . 

 It is certain that similar muscular combinations in two or more birds 

 do not necessarily mean relationship, while on the contrary similar 

 requirements are often met in similar ways. . . ."' — J. A. A. 



Stone's Birds of Eastern Pennsylvania and New Jersey.' ^ — ^Mr. 

 Stone, with the assistance of his fellow-members of the Delaware Valley 

 Ornithological Club, has presented us with a faunal list which, except in 

 unimportant details, mav well stand as a model for works of this nature. 



Chapter I, on ' The Geographical Distribution of Birds,' opens with 

 remarks on the 'General Law's of Geographical Distribution,' and is 

 followed by a detailed consideration of the ' Faunal Areas of Eastern 

 Pennsylvania and New Jersey — their Physical Features and Character- 

 istic Birds,' the value of which is much enhanced by a colored map. 



Chapter II, on ' Bird Migration,' treats of the subject from both a 

 general and local standpoint and should be read by every one interested 

 in the study of this branch of ornithology. This chapter concludes with 

 a nominal list of the ' Birds found within Ten Miles of Philadelphia,' 

 some 260 in number, grouped under the following, in the main, well- 

 chosen headings : I. Resident Birds. II. Species which are of lare 

 or irregular occurrence in winter, but common summer residents. 



' The I Birds of Eastern Pennsylvania | and | New Jersey | With Intro- 

 ductory Chapters on | Geographical Distribution and Migration | Prepared 

 under the direction of the | Delaware Valley Ornithological Club | By | 

 Witmer Stone | Conservator Ornithological Section Academy of Natural 

 Sciences of Philadelphia | — | Philadelphia | Delaware \' alley (Jrnithological 

 Club I 1894. — 8vo., pp. vii 185, frontispiece and two maps. 



