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The Mttseum Gazette 



CORRESPONDENCE. 



Date of the Exodus.— An esteemed correspondent calis our 

 attention to the fact that the date of the Exodus is given in " The 

 Centuries " as two centuries later than in other chronologies, and asks 

 for authorities. Our dates, as given in The Centuries, are based upon 

 Flinders Petrie's statements as being those of the most recent 

 authority. He points out that the duration of the period of the Judges 

 was probably much over-estimated, and that it ought to be shortened 

 by two centuries. It was by calculating backwards that the supposed 

 date of Moses was reached, which was thus much antedated. In 

 Egyptian history proper no data exist. All authorities agree that the 

 Exodus must be placed in the reign of Merenptah, and the reign 

 •of this king is assigned by Petrie to the twelfth century, B.C. See his 



History of Egypt," p. 251. We have therefore, we believe, the best 

 authority for giving the name of Moses to the twelfth century B.C. 

 as is done in our u Centuries." 



Juvenis asks whether the cuckoo-spit is caused by an Aphis. 

 The insect which causes the "Cuckoo-spits" is not a true Aphis. 

 They are the home of the larva of the frog-hopper, a greenish insect 

 allied to the Aphis, but in which the hinder legs are lengthened and 

 enable it to jump. Aphrophora spumaria is the scientific name of 

 the species commonest in England, but there is a smaller one 

 bifasciata, which is also very common. 



The larva is developed in the midst of the mass of froth which it 

 has formed. It is a naked greenish or yellow grub, which in its later 

 stages developes six legs, compound eyes and two pairs of short wings. 

 Living in a warm bath of bubbles which protects them from heat, 

 cold and wind, these naked insects may be supposed to enjoy luxurious 

 life. Their environment is an object of disgust to all enemies. 



We shall write more at length on these interesting insects in a 

 future number. 



CHRONOLOGIST.— We agree with you that we certainly ought to 

 give up the most confusing practice of counting time backwards in 

 the B.C. periods and forwards in the Christian ones. Julius Csesar was 

 born in the year known as 100 B.C., and his age, therefore, runs with 

 that century. He was 56 when he was assassinated. Now, if we 

 might speak of this as the fifty-sixth year of the first B.C. century, 



