G. GENERAL NATURAL HISTORY AND ZOOLOGY. 203 



twenty-three are in any way poisonous. 15 A 9 August 6, 

 1870,179. 



POISOX GLAXD OF AX EAST IXDIAX SERPEXT. 



We are most of us familiar with the structure of the poison 

 glands in the American serpents, as illustrated in the rattle- 

 snake and copperhead. These, as is well known, lie on each 

 side of the head, and give to it a peculiar breadth as com- 

 pared with the narrow neck, and show unmistakably the 

 venomous nature of any given specimen. In a certain form 

 of East Indian serpent, however, the Callophis mtestmalis, 

 these glands extend from the head for about one third of the 

 entire length of the body, lying free in their cavity, and 

 causing the heart to occupy a place greatly posterior to its 

 usual position in other species of snakes. 12 A, July 28, 265. 



TURTLES OF XORTHERX AXD SOUTHERX AMERICA. 



In a lecture upon " The Origin of Species," by Professor 

 Cope, delivered at Germantown, he remarked upon the differ- 

 ences between the turtles of the northern and southern hem- 

 ispheres. These are mainly that the under side of the shell, 

 in the southern forms, has eleven plates, while that of the 

 northern has but ten. The northern turtle withdraws its 

 head between the two shells by bending its vertebral col- 

 umn, but the southern throws its head around one side under 

 the shell, much as a bird buries its head under its wing. In 

 the turtle of the southern hemisphere both bones of the pelvis 

 are united to the lower shell by a vertebral brace ; in the 

 northern, they are entirely separated. These are the strong 

 characteristics of the two varieties ; but in the upper bed of 

 the mesozoic age, in the green sands of New Jersey, turtles 

 are found which have some of the characteristics of those of 

 the southern hemisphere. In these, however, the bones of the 

 pelvis are not joined to the lower shell, but there are slight 

 projections on the shell immediately under the pelvis which 

 nearly approach a junction. Copers Lecture. 



FROGS IX XEW ZEALAXD. 



The adaptation of certain animals to conditions of exist- 

 ence apparently different from those considered necessary to 

 the preservation of life has frequently been noted, and a curi- 



