Introduction 



generic names, but has uniformly adopted technical names that 

 have been well established. Thus there will be no lists of synonyms 

 in this book. His policy has been to devote more time in pre- 

 paring a popular presentation of his subject, than to add another, 

 to the many searches for "priority." 



Following is an example of a title, and its different parts: 



PIGMY RATTLESNAKE, a 



Sisfrurus luiliarius, (Linn.), b 



a. — The popular name. 

 b. — The technical name and authority. 

 The parts of the technical or scientific name may be 

 described thus: 



Sistrurus a. miiiarius, b. (Linn.) c 

 a. — The generic name. 

 h. — The specific name. 

 c. — The authority. 



In strictly scientific writings, the placing of the name of 

 the authority in a parenthesis, signifies that the name of the 

 genus has been changed from that in which the species was 

 placed in the original description. 



Under the head of scientific names comes another subject. 

 This is discrimination in the recogniiion of species and sub- 

 species — varieties. In a purely scientific book, those species 

 and varieties that have been rejected as doubtful, or forming 

 mere varietal phases of well-established species, are placed in 

 the list of synonyms, beneath the name; relating to their re- 

 jection is usually an argument, explaining the cause of their 

 exclusion. As this is a subject that will interest the technical 

 herpetologist only, we will pass it with the explanation that 

 such lists have not been treated in this work, and the final result 

 of the writer's discrimination stands illustrated in the array 

 of those species and varieties (sub-species) that have been 

 recognised. 



System of measurement. — Nearly every description has a 

 table of measurements; these lists have been prepared in uniform 

 style throughout; most of them stand as average dimensions, 

 taken from a series of specimens. 



The measurements of the length and width of shells of 



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