May i6, 1907] 



NA TURE 



53 



we do not sec in what respect the representation of 

 waves bv their wave-fronts is associated witli less 

 fiction than what the authors refer to as " tlie time- 

 honoured fiction of rays." Whether the wave is re- 

 presented by its front or its normal is a question 

 merely of convenience or lucidity. The fiction which 

 affects both equally consists in regarding the wave 

 as a simple spherical one, and when the question is 

 the higher one of the deviation from sphericity, we 

 think the advantage lies all on the side nf the method 

 of ravs. We conclude by wishing lliis vcilunir mII 

 success; it deserves to be widely read. 



■I'HE PRINCE OF ENTOMOr.OGV. 

 Lcs Debuts d'lin Savani Naiurcilistc. l.c Prince de 

 I'Entoniologie. Pierre-Andre' Latreillc a Brive dc 

 1762 a 1798. By Louis de Nussac. l'|). vii + j()4. 

 (Paris : G. Steinheil, 1907.) Price 5 francs. 



THE subject of this memoir was the natural son 

 of Baron d'Espagnac, and some doubt exists 

 as to the exact date and place of his birth; his 

 biographers, however, are agreed in giving the 

 former as 1762, and Brive, in the department of 

 Correze, as the place where he first saw the light of 

 day. He was educated at Brive and at Paris, took 

 orders in 178 1, and eight years later became a fully 

 ordained priest. The Revolution altered the ecclesi- 

 astical future of Latrellle, for in 1793 he was arrested 

 on the charge of neglecting to take the oath of 

 allegiance to the new Government, was thrown into 

 prison, and sentenced to exile in Cayenne in com- 

 pany with other recalcitrant priests. 



Latreille was saved from this fate by the influence 

 of friends and by a fortunate accident, the story of 

 which is of considerable interest. On the wall of 

 his cell, which he shared with an invalid prisoner, 

 Latreille, who was already an expert entomologist, 

 found a specimen of a beetle that he recognised as 

 new to science ; the surgeon attending the invalid 

 observed Latreille's excitement, and on discovering 

 the cause of it asked if he might give the specimen 

 to a scientific friend, M. Bory. Next day the surgeon 

 brought back word that M. Bory was unable to 

 identify the new beetle, and Latreille, perceiving that 

 he was dealing with a brother entomologist, sent 

 him the message : — " Vous lui direz que jc suis 

 I'Abbe Latreille, qui va aller mourir a la Guyane 

 avant d'avoir public son ' Examen dcs Genres de 

 Fabricius.' " Steps were immediately taken to free 

 the captive, and he was literally snatched from the 

 ship bearing the exiles to Cayenne ; the ship sub- 

 sequently foundered off the French coast, and all 

 hands were lost. Latreille, in his classic work on 

 insects and crustaceans, describes the insect that was 

 the means of his salvation as Necrohia nificoUis, and 

 details the circumstances of its discovery; in his 

 " I ,, ncra crustaceorum et insectoruni " he apostro- 

 plii-i s it as " Insectum mihi carissimum," and a re- 

 proentation of it is carved on the bust of the great 

 entomologist in the museum at Brive with the in- 

 scription " Necrobia ruficollis Latreillii salus anno 

 MDCCXCIIL 



NO. 1959 VOL- 76] 



After these adventures Latreille returned to Brive, 

 and tranqiiilly resumed his entomological studies. 

 The end of the eighteenth century in France was 

 marked by the immense stimulus given to the scien- 

 tific study of agriculture ; societies for the encourage- 

 ment and advancement of agriculture sprang up 

 everywhere, and met with ofilcial sanction and help. 

 Experiments on the cultivation of all sorts of crops 

 were carried out, new agricultural machines were 

 invented and tested, efforts were made to combat 

 insect pests, and the methods of other countries were 

 studied. In fact, France more than a century ago 

 had arrived at a stage in agricultural progress which 

 the modern Englishman may well envy. To-day an 

 industrious peasantry, firmly rooted to the soil, is the 

 prop and mainstay of France, and who can doubt 

 lliat their existence is largely due to the work of 

 those early agricultural societies, called into being 

 themselves by the revulsion of feeling against a 

 Ivrannical and effete landed aristocracy? The cry 

 of " Back to the Land " is only heard in those 

 countries where the needs of agriculture are regarded 

 by legislators with languid indifference. 



In a milieu of eager and scientific inquiry a man 

 like Latreille was bound to make his mark ; he was 

 appointed professor of natural history at Brive, and 

 in 1798 was elected a member of the Institut National 

 des Sciences et des Arts of France. During these 

 years he was in active correspondence with Fabricius, 

 to whom he owes his title of Princcps Entomologiae, 

 with Olivier, Bosc d'Antic, and other entomologists 

 01 the day, and he was personally known to the 

 P.iris zoologists, the great Cuvi<M-, Dum^ril, 

 Daubenton, and Lacep6de. Several of his letters are 

 quoted by M. de Nussac, and these alone show, 

 even if we had not his published works to convince 

 us, that Latreille possessed the true Frenchman's 

 power of generalisation and ability to seize on 

 characters of prime importance for systems of classifi- 

 cation. In 1796 Latreille published at Brive his first 

 great work, " Precis des Caracteres geniViques des 

 Insectes," which earned for him the plaudits of the 

 entomological world of the day; it was followed by 

 " Essai sur I'Histoire des t'ourmis de la France," 

 and shortly afterwards Latreille migrated to Paris to 

 take up a post in the Natural History Museum. 

 There his biographer leaves him, but promises a 

 second volume on his subsequent career; M. 

 de Nussac will find it difiicult to write a more interest- 

 ing volume than his first. K- S. 



OUR BOOK SHELF. 



The Steam Turbine as Applied to Marine Purposes. 



By Prof. J. H. Biies. Pp. vii-l-126. (London: 



Charles Griffin and Co., Ltd., 1906.) Price 6s. 



net. 



Pkof. Bii.es delivered the Keith lectures before the 



Royal Scottish Society of Arts in Edinburgh during 



the spring of 1906, and as only a condensed surn- 



mary of the lectures was published by the society in 



its monthly journal, while many requests were 



made to the lecturer for complete copies of the 



lectures, he decided to i)ub!i>li them in book form. 



I 



