SNAILS OF THE FOREST AND FIELD 



Promptly at one o'clock on Saturday afternoon our quartette of con- 

 chologists were at the museum, and were as promptly met by Profes- 

 sor Parker, who was waiting for us. We lost no time in ascending 

 to the upper gallery where the mollusks were located. We went from 

 case to case, and the Professor told us interesting and instructive facts 

 concerning the specimens in each. 



" Land shells are found almost everywhere," said Professor Parker, 

 " in valleys, high upon mountains, and even in deserts. Many species 

 live on Alpine heights of over thirteen thousand feet, while others 

 love the beaches near the ocean where they are wet with the salt 



spray. Some are subterranean in habit, living under- 

 ground in burrows, while others live among the 

 limbs of tall trees, never visiting the ground. They 

 Vitrea ceiiaria, a may } }e found in the cold climate of Alaska and in 



common .European 



land snail, it has also the tropical zone, under the equator. As a rule, 



been introduced into n ,, j i TJ i 



the greenhouses of the they preier moist localities where there is abundant 



United States. (Bin- vegetat i on> anc j w j iere t } le groim d is strewn With 



rotting logs, beds of decaying leaves, or moss-covered 

 rocks. In the northern part of the United States, open woods may be 

 said to be their best habitat. 



" As you have already learned, land snails breathe by means of a 

 so-called lung, which is a sac lined with a network of blood-vessels, 

 occupying the last turn, or whorl of the shell. The air taken into 

 the lung purifies the blood. They are called Pulmonata, or air-breathers, 

 for the reason that they possess a lung and breathe air directly, instead 

 of through the medium of water. 



" The shells of the Pulmonata vary to a wonderful degree in size, 

 shape, and coloration. Some are so small that they can scarcely be 

 seen with the naked eye, while others attain a length of six or more 

 inches; some have the aperture of the shell modified by numerous 

 folds, or teeth, while others are smooth. The colors vary from whitish 

 or horn-colored, to the gorgeously colored Helices of the tropics, with 

 their bands and blotches of red, brown, white, and green. With all 

 this diversity, the land shells may be easily distinguished from their 



46 



