48 Observations on I>i\ Carus's Discovery 



the two philosophers ; who had either invited no guest to their 

 banquet, or found none who relished in prospect the piece de 

 resistance, A huge dish of snails was placed before them: 

 but philosophers are but men, after all ; and the stomachs of 

 both the doctors began to revolt against the proposed experi- 

 ment. Nevertheless, if they looked with disgust on the snails, 

 they retained their awe for each other : so that each, conceiv- 

 ing the symptoms of internal revolt peculiar to himself, began, 

 with infinite exertion, to swallow, in very small quantities, 

 the mess which he internally loathed. Dr. Black, at length, 

 ' showed the white feather,' but in a very delicate manner, as 

 if to sound the opinion of his messmate. ' Doctor,* he said, 

 in his precise and quiet manner, * Doctor, — do you not think 

 that they taste a little — a very little, green ?' ' D — d green, 

 d — d green, indeed, — tak' them awa', tak' them awa',' voci- 

 ferated Dr. Hutton, starting up from table, and giving full 

 vent to his feelings of abhorrence. And so ended all hopes of 

 introducing snails into the modern cuisine: and thus philoso- 

 phy can no more cure a nausea than honour can set a broken 

 limb." ( Quart, Review, xxxvi. 197.) 



I am, Sir, &c. G. J. 



Art. XI. Observations relative to Dr. Caruss Discovery of the 

 Circulation of the Blood in Insects. By William Spence, Esq. 

 F.L.S. 



Sir, 

 One of the obscurest points of the physiology of insects 

 has always been that of the circulation of their blood. The 

 most superficial observer of many of the large thin-skinned 

 larvae could scarcely fail to observe the evident regular pulsa^ 

 tion of a fluid in a vessel running along the back, and it was 

 naturally considered that this fluid is analogous to the blood 

 of larger animals : but as even the microscopic observations 

 of Swammerdam and Lyonet had never detected any thing 

 like blood-vessels in other parts of the body of insects, a circu- 

 lating system has been generally denied to this class, which in 

 this circumstance has been thought to differ from some of the 

 classes immediately connected with it. It was reserved for 

 that eminent physiologist, Dr. Cams of Dresden, physician to 

 the King of Saxony, to remove this obscurity by the interesting 

 and important discovery which he made and published a few 

 years ago (and the substance of which is given in an appendix 

 to Mr. Gore's translation of his Introduction to the Comparative 



