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Art. XII. ANALYSIS OF SCIENTIFIC BOOKS. 



I . Philosophical Transactions of the Royal Society of Lon- 

 don, for the year 1825. Part the Second. 



In our quarterly reports of the proceedings of the Royal Society, 

 we have given brief and general abstracts of the principal papers 

 contained in the volume before us ; a more detailed and accurate 

 abridgement of their contents will form the subject of the follow- 

 ing article. 



j. On the Anatomy of the Mole-cricket. By J. Kidd, M. D., 

 F. R. S., Regius Professor of Medicine in the University of 

 Oxford. 



This singular insect is described under various names ; as the 

 earth-crab, from its general appearance ; vermis cucurbitarius, 

 from the mischief it does to cucumber-beds. By the French na- 

 turalists it is called courtiliere. 



The best account of it is in a well-known entomological work 

 by Rbsel, published at Nuremberg, in 1749. This account is ac- 

 companied by the best engravings also of the external characters 

 of the animal in its different states ; and the value of these en- 

 gravings is greatly enhanced by the accuracy with which they 

 are coloured. 



Rosel says, that about the month of June or July, rarely later, 

 the gravid female gryllotalpa excavates a cavity, from four to five 

 inches beneath the surface of the earth, in which she deposits her 

 eggs in one heap, to the number of three hundred or more, and 

 dies within a few weeks afterwards. At the end of about a month, 

 the young mole-crickets are produced ; and appear, on a hasty 

 survey, to bear a general resemblance to the ant. Between the 

 time of their birth and the commencement of winter, the young 

 animals cast their skin three times ; they lie dormant during the 

 winter, deeper in the earth in proportion to the inclemency of 

 the season ; and during this period cast their skin for the fourth 

 time. About May they leave their winter-quarters, and at this 

 time are furnished with the rudiments of their future wings, four 

 in number ; which differ remarkably in size and form and position 

 from those of the perfect insect, in which the inferior wings are 

 folded in a very curious manner, while in the imperfect insect 

 they are always open. 



During the month of June or July they cast their skin for 

 the fifth and la3t time ; after which the wings acquire a perma- 



