422 THE METHOD OF ORGANIC EVOLUTION. 



being recorded. Almost tlie whole of these present, more or less, want 

 of symmetry, while a large proportion, as the double-handed and double- 

 footed children and the six or seven toed cats, can only be classed as 

 monstrosities. 



In succeeding chapters the variations in the antenuiB and leg joints 

 of insects; in the radial parts of medusie and encrinites; in the medial 

 structures of fish, insects, mollusks, etc., which become sometimes 

 double; in the eyes and coloration of tiattish; in duplicate or branch- 

 ing legs of insects and crustaceans; in extra limbs of batrachia; and, 

 lastly, double monsters, are all discussed at great length, and are illus- 

 trated by a number of very interesting woodcuts. But almost the whole 

 of these can only be classed as malformations or monstrosities which 

 are entirely without any direct bearing on the problem of the '' origin 

 of species." 



Nothing can better show the small value of the book from this, which 

 is the author's own, point of view than the large amount of space 

 devoted to the various monstrosities of the hands and feet of man and of 

 some of the mammalia. Not only throughout all mammals, but also in 

 the case of birds, reptiles, and amphibia, five is the maximum number 

 of the toes or fingers. These may vary in size or in proportions, they 

 may be reduced in number by coalescence, or by the loss of the lateral 

 digits; they may be strangely modified in form and function, as in the 

 flappers of the whale or in the wing of the bat, yet never once in the 

 whole long series of land vertebrates do they exceed five in number. 

 Yet we have six, seven, or eight fingered, double-handed, or double- 

 footed children; similar malformations in monkeys; six and seven toed 

 cats; four, five, or six toed pigs; double footed birds, and other mon- 

 strosities, described at great length, and all their peculiarities discussed 

 in the most minute detail and from various points of view, in a work 

 presented to us as "a contribution to tlje study of the problem of 

 species." Many of these malformations have been observed among 

 animals in a state of nature, and, in fact, Mr. Batesou believes that they 

 occur as frequently among wild as among domesticated animals. Con- 

 sidering how rarely the former cases can be observed, they must be 

 everywhere occurring; yet in no single instance do they seem to have 

 established themselves as a race or local variety on however small 

 a scale. Yet we know that in the case of the six-toed cats, and prob- 

 ably in other cases, they are easily transmissible; and we must there- 

 fore conclude that all these irregularities and monstrosities are in a 

 high degree disadvantageous, since when subject to free competition 

 with the normal form in a state of nature they never survive, even for 

 a few generations. 



As the volume we are discussing is entirely devoted to variations in 

 the number or position of the serial parts of organisms in relation to 

 the origin of species, it becomes necessary to lay some stress upon the 

 very familiar, but apparently overlooked, fact that, among all the higher 



