Zoologi/. 373 



than that the eastern Indians will rid their houses of the most venomous 

 snakes, by charming them with the sound of a flute, which calls them out 

 of their holes. Instances of the same kind, however incredible they may 

 appear, are given, not only by ancient writers, such as Pliny and Seneca, but 

 by modern authors of undoubted credit, such as Sir William Jones, Bruce, 

 Shaw, Greaves, Chardin, Forbes, and Chateaubriand. 



Et/es of Crabs and Lobstei's. — Dr. W. E. Leach has invented a term (Po- 

 dophthahna) to distinguish crustaceous animals, from the mechanism of 

 their eyes, which are placed at the extremity of pedicles, somewhat like 

 the glass of a telescope. M. Lamarck says that these eyes are not retrac- 

 tile, like the horns of the snail, but he has observed, in living crabs and lob- 

 sters, that the eyes, at the least touch, are drawn back a little into the 

 sheath, and concealed in the same fossette where they are placed. (Z^a- 

 viarckj Discoursd^Ouverture,]). 15.) 



The Tyrian Purple Dye. — The colour extracted by the ancients from 

 certain shellfish, and so highly esteemed, as to be reserved exclusively for 

 princes, has been produced by modern experiment, though its value, it 

 should seem, has passed away with the fashions of antiquity. More than 

 one sort of shellfish furnishes a purple dye, but the principal belong to the 

 two genera Mureyi and ^uccinum, which can still be procured in great 

 plenty on the shores of the Mediterranean. The great expense of the pro- 

 cess would preclude it, we imagine, from answering the purpose of modern 

 speculation, for one shell only affords a single drop of the dye; and it re- 

 quired (at least in the ancient process) six pounds of dye to one pound of 

 wool, which, when dyed, sold at the enormous price of a thousand Roman 

 denarii, or about 36/. 



Hatching of Female Eggs. — It has long been remarked, by collectors, 

 that the male broods of insects always appear earlier thein the female 

 broods ; but we do not know whether it has also been remarked, that the 

 eggs from which females are produced are longer in hatching. I can state 

 one instance in which this was distinctly the case. Upon the leaf of a 

 poplar tree I found three eggs of the Puss moth (Cerura vlnula), two of 

 which were hatched about two weeks before the other. The first were 

 males, the last a female. As they were on the same leaf, and presumed, of 

 course, to be laid by the same parent, at the same time, the difference of 

 hatching could not arise from difference of weather, exposure, &c. — •■ 

 J. Rennie. 



Doubtful Discoveries. — It may serve, in some measure, to confirm M, 

 Dutrochet's recent opinion of the non-existence of miscrosoopic animal- 

 cula, that the celebrated Spallanzani persuaded himself that he could see 

 Animalcula infusoria which could be seen by nobody else. He attributed 

 his own superiority of vision, in this respect, to long practice in using the 

 microscope. The philosopher exulted in his enviable distinction, when a 

 peasant, to whom he showed his animalcula, could perceive nothing but 

 muddy water. 



Mistakes of Instinct. — In the account of that most singular parasitic 

 flower (having neither leaves nor stem, it can scarcely be called a plant), the 

 RafHesk Arnoldii {Mag. of Nat. Hist., p. 68.), it is mentioned that it smells 

 like tainted beef; and, on its first discovery by Dr. Arnold, a swarm of flies 

 were gathered round it, for the purpose, he imagined, of depositing^ their 

 eggs upon it, supposing it, no doubt, to be in reality tainted beef. This is 

 one instance in hundreds which might be enumerated, of what may be called 

 the mistakes of instinct, where it depends upon the information of the senses; 

 and, in this respect, similar mistakes frequently occur, where the higher 

 powers of human rationality are deceived by analogous phenomena. The fine 

 nutty flavour of cherry laurel-water and of prussic acid, both most deadly 

 poisons, would be certain to deceive the inexperienced ; and Majendie's 

 maid-servant actually fell an immediate victim to her desire of tasting the 



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