NATURAL HISTORY. 



467 



the snail also resembles the under cushion 

 of the turtle, only, of course, it is much 

 more delicate and softer. 



The snail has his enemy, however. Most 

 of the empty shells I found had a smoothly 

 bored, round hole in one side, which told 

 its own story. I was fortunate in finding 

 one perfect shell. Lining it was a thin 

 white sheet or crust, clinging so tightly 

 just within the shell that I could not easily 

 raise it with a penknife point. However, 

 I placed the shell in salt water. A hidden 

 power then lifted the lining, pushed it for- 

 ward almost imperceptibly, and then 

 dropped it back, as if the power was tired. 

 After a moment the movement was re- 

 peated. From under the lining a bunch 

 of tiny yellow yolks was pushed out 

 one day when I was absent. Another 

 day, from the outside of the shell, 

 crawled a tiny white barnacle, like a white 

 bedbug or hemiptera. That made its way, 

 by sailing and crawling, into the shell, 

 where it disappeared at the back of the 

 white lining. In one of these shells one 

 day the power ceased to act, and as the 

 lining was already raised, I pulled it out. 

 On the under side clung a partially devel- 

 oped snail, as nearly as I could make out 

 without a microscope. 



All the process concerning this other- 

 wise empty shell was unique and most in- 

 teresting. I failed to determine a differ- 

 ence in sex, but trust for more develop- 

 ments another summer. My first speci- 

 men lived one week, captive in the house. 

 None of the others survived a second day, 

 yet in all cases new salt water and fresh 

 sand were given daily and often twice. I 

 should like to know how small and how 

 large the snail may be found, fully devel- 

 oped. The smallest perfect shell I found 

 was less than V 2 an inch in circumference, 

 and my largest would be about 13 inches 

 if it were not broken. 



PRAIRIE DOGS IN THE NEW YORK ZOOLOGI- 

 CAL PARK. 



J. ALLEN LORING. 



The prairie dog inclosure in the New 

 York Zoological Park is probably the 

 finest structure of its kind in the world. 

 It is circular, is 80 feet in diameter, and is 

 built on solid masonry that reaches to bed 

 rock. 



On September 13th the society received 

 from Mr. Howard Eaton, of Medora, 

 N. Dak., a gift of 36 Missouri prairie dogs 

 to be assigned to the Recreation group. 

 They were immediately put in their new 

 home. Later, a second lot was received 

 from Kansas, part of which were put in 

 with the others, and in pursuance with the 

 directors' long cherished plan to colonize 

 in the big game ranges certain small 

 species which in nature are associated with 



them, the others were placed in a temporary 

 inclosure in the Antelope Range. This pen 

 was hastily built, and meant only to hold 

 the animals until they had started their 

 burrows and become established, when it 

 was thought they would remain perma- 

 nently. In these calculations the society 

 was correct, for although a tew wandered 

 away and failed to return, enough remained 

 to form a satisfactory colony. Visitors are 

 now much surprised at seeing these in- 

 teresting little animals living as free and 

 natural as in their natural haunts. They 

 have become accustomed to the antelope, 

 and may be seen feeding about their feet 

 with the utmost confidence. There is ab- 

 solutely nothing to prevent the dogs from 

 escaping if they chose, for the large 

 meshes of the Page wire fence would ad- 

 mit an animal of twice their size. They 

 have made permanent burrows and regard 

 them as their homes. 



During the first month of their arrival 

 they spent much of the time digging their 

 burrows. They worked industriously, 

 loosening the dirt with their paws and 

 throwing it out with their hind feet. The 

 burrows being finished, they began carry- 

 ing in grass for their nests; filling their 

 .mouths as full as they would hold and 

 tucking in the ends with their paws. On 

 visiting their inclosure one evening after 

 a rain I found one dog outside, patching 

 the damage done by the water. With his 

 front feet he would loosen the dirt a short 

 distance from the hole, and when his claws 

 became so gummed he could not work, he 

 cleaned them with his teeth and went on. 

 When he had scratched up a quantity of 

 earth he threw it under his belly, and witli 

 his hind feet scratched it up to the en- 

 trance, but more frequently he turned 

 about and scooped it along with his hands, 

 as a boy would scoop up sand. A iter he 

 had pushed the dirt up on the entrance he 

 raised himself on his feet, arched his back, 

 and hammered it down about the mouth of 

 the burrow with his nose; then went in- 

 side and hammered the dirt that had be- 

 come soft from the rain. I watched him 

 some time scraping up the dirt and 

 packing it about the burrow so the water 

 would not run in, and after he had finished 

 I entered the enclosure and examined ln- 

 work. I found the entire rim of the bur- 

 row was firmly tamped, as though someone 

 had punched his fingers into the soft earth. 

 Several other burrows were treated the 

 same way. 



After every rain some of our < ; . 

 may be found working about their holes, 

 either carrying out the wet bedding or 

 taking in new. On cold days they remain 

 under ground, but as soon as the sun 

 comes out they appear, and may be seen 

 sitting about their burrows or cropping off 



