229 



living beads of amber, which moved slowly about, and as the stones 

 became dry disappeared beneath them. 



Succiiiea avara, Say. — This species is far from common hare. Like 

 S. ovalis, it inhabits moist phicas in the wooil-i and op3n fields, bat un- 

 like that species, never congregates in large numbers. I have taken about 

 a dozen examples in a space of five or six square yards in the locality 

 which afforded nie the very large .S'. ovalis just referred to. They are 

 of much greater size than the shells usually found, averaging 8-5 by 

 5-G mm. I have one shell still larger from Billings' Bush. Tt meas' 

 nres 10-4 by G mm. 



There can scarcely bo imagined a covering better adapted for pro- 

 tective purposes than that with which S. avara is provided. Oveidap- 

 ping the thin edge of the shell, the mantle secretes around the peri- 

 stome a viscid substance to which particles of earth adhere and remain 

 firmly attacheil. The shell closely resembles a speck of mud or frag- 

 ment of bark; and as it is very slow in its movements, must often 

 escape the searching eyes of enemies, whether bird or naturalist. 



Saccinea ohliqua, Say.- —This is the largest of the three species 

 found here. It does not, like the others, frequent wet stations only, but 

 is often met with in dry woods far removed fron\ ponds and streams. It 

 is quite a common shell, although not often seen except after warm showei's 

 in summer when they appear so suddenly and in such numbers that, like 

 the young toads which sometimes accompany them, they might be 

 thought to have fallen with the rain. The fact is that their dwellings 

 being flooded they seek higher levels; and the wet ground being well suited 

 for locomotion, make little expeditions on duty or pleasure until they 

 find the earth becoming dry again, when they return to their hiding 

 places in the grass or under stones Tney are unwilling to I'emain un- 

 <ler water, but if confined there are, I find by experiment, able to live 

 without free ai)- for at least forty-eight hours. The largest shell found 

 measures 18'5 by 10 mm., but the average is much less, being 14 by 

 8-5 mm. Shells a little smaller are very common in the marl beds, 

 and specimens collected there hibernating on the 5th November, 

 1834, have since been su!)jected to cold tar below the freezing point; 

 and yet, if now placed in te[)id water, they become active in a few 

 minutes. 



