60 



SCIENCE 



[N. S. Vol. XXXVII. No. 941 



THE DORSAL SCALE ROWS OP SNAKES 



In these days when so much attention is 

 being given to the variations and minute char- 

 acters of animals it seems remarkable that 

 such an important trait as the number of dor- 

 sal scale rows in the snakes should receive 

 careless treatment. This character is given 

 considerable weight in delineating species and 

 deserves careful attention. From the descrip- 

 tions one could only conclude that each spe- 

 cies has a rather definite number, 17, 19 or 21, 

 as the case may be, and that the variations 

 are abrupt. The facts are far from being as 

 simple as this. As a rule the number of scale 

 rows decreases posteriorly, and there is often 

 a decrease anteriorly, so that the maximum 

 number of rows (the number now given in 

 descriptions) may either extend from the head 

 to beyond the middle of the body, or be re- 

 stricted to a longer or shorter distance on the 

 middle, sometimes only for the length of two 

 or three scales. Furthermore, the species that 

 exhibit a variation of two or more entire rows 

 on the anterior part of the body also show the 

 intermediate stages in which the extra rows 

 are present on the middle of the body only, 

 which leaves no doubt that the variations in 

 this character are not abrupt but gradual. 



From these facts it is evident that the aver- 

 age number of rows characteristic of a 

 species in any region can only be expressed by 

 a formula that gives the number of rows on the 

 different parts of the body. It is not enough to 

 say that a species has a maximum of 21 rows ; 

 one should at least know whether the number is 

 21 for the greater part of the length or only 

 on the middle of the body. Quite evidently a 

 form with an average of 21-19-17 scale rows, 

 which means 21 to beyond the middle and 19 

 and then 17 posteriorly, is not the same as one 

 in which the scale formula averages 19-21-19- 

 17, any more than one with 21-19-17 rows is 

 the same as one with 19-17 rows, although 

 such variations are thrown together under the 

 present way of recording the rows. 



It is a simple matter to count the number 

 of rows on the different parts of the body and 

 this may be conveniently expressed by the 



formula given above. At least this much 

 should be done by the herpetologist, if not for 

 the systematist then for the student of geo- 

 graphic variation, for only with this data can 

 one determine the variation in this character 

 and the type in each locality. 



AlexainDer G. Euthven 



MlJSEDM OP NaTUBAL HISTORY, 



University op Michigan 



THE question of TEXT-BOOKS IN COMPOSITION 



When a Harvard man thinks of books on 

 English composition he thinks of Professor 

 Wendell, and before him Professor Hill, and 

 before him the dark. Professor Hill's books, 

 though immensely comforting and instructive, 

 ought to be considered as reference books 

 rather than as texts. Therefore, in the winter 

 of 1890-91, when Professor Wendell found 

 himself confronted with the problem of lec- 

 turing on composition to a Lowell Institute 

 audience, he looked about him to see what had 

 already been done. He was surprised to find 

 that nothing then in print quite served the 

 turn. All these earlier fellows were too tech- 

 nical and too much absorbed in detail. They 

 laid down hard and fast rules. They had no 

 patience with the growing tendency to say, 

 " It is me." Students could scarcely tolerate 

 their etymology, their prosody, their similes 

 and their metaphors. Professor Wendell felt 

 already, we may assume, something of his 

 present fine impatience with the details of 

 scholarship; he was already, on his academic 

 side, professionally unconventional. Here, 

 then, was a man peculiarly gifted by nature 

 for the work of cleaning house in rhetoric. 

 There resulted the Lowell lectures, and, in 

 time, the " English Composition." 



Since then nobody, I believe, has dared to 

 depart from Professor Wendell's ways. We 

 have had composition books written by nearly 

 everybody, for nearly every important institu- 

 tion and academic grade; but none in any 

 essential respect different from the first. Lat- 

 terly they become more full of illustrative 

 material and exercises. They present ex- 

 amples of faulty and correct writing from 



