52 NOTES. 



Note *", page 29, line 1. 

 Helix ! may suit thy taste and form, 

 And I like thee ivould shun the storm. 

 The movements of the common Helix are uncommonly slow, 

 the viscous nature of its juices, -which are extremely tardy in 

 their circulation, produce a considerable degree of sluggishness 

 in the movements of the animal. This ingenious idea was first 

 suggested by JNIr. Braidlv, he observed the circulation in a snail 

 just hatched, the body and shell of which being quite transparent, 

 enabled him to discover that the pulsations of the heart succeeded 

 each other at the distance of three seconds. Conjecturing how- 

 ever, that the juices in so voung a subject would circulate more 

 (juickly than in an older one, he had resource to some, the shells 

 of which had been damaged by some previous accident. In these 

 the beats were five seconds distant from each other, the circulation 

 having probably been accelerated by the injury they had sustain- 

 ed, as, in the course of three hours afterwards, seven seconds 

 elapsed between each, at which period, some of the largest had 

 begun to renew their shells, by throwing out a considerable 

 quantity of viscous juice through the pores of the undefended part. 

 The peculiar nature of the juices of the Helix, seems to have a 

 reference to its mode of life, for no degree of natural or artificial 

 cold has ever been known sufficiently powerful to congeal them. 

 Helix Pomotia, or Exotic Snail, differs little in appearance from 

 the common. This species was first introduced into England, by 

 the celebrated Sir Kenelm Digby, as food or medicine for his 

 lady, who died of consumption. Various attempts have been 

 made to naturalize them in Northamptonshire, but without suc- 

 cess, as they uniformly refuse to emigrate from the southern 

 shores of England ; they are tenacious of life, and equally 

 susceptible of cold ; towards winter they cover their sub-lunate 



